Top Replacement

Q: Top Replacement

After checking with various shops about installing a conv. top on my 1968 Firebird Conv., I’m considering doing this myself. (just can’t see paying $400-$500 just for labor) Anyhow, I did a vinyl top before and it took a good day to do but wasn’t really that difficult. Any thoughts, suggestions on a conv. top ‘do-it-yourself’ project ? How about aby reference material for doing a conv. top ? Fisher Body Manual, Restoration Guides, Articles, etc. ?

A: Yeah, I did one on my first 1969 Firebird back in ’76, spent a weekend doing it. No reference materials, just tackled it in almost complete ignorance, and it came out perfectly. Start at the rear, don’t be afraid to pull it tight as you attach it moving to the front. I’ll give you details later if you decide to try it. Keep in mind I’m no expert, and it’s been more than 20 years, but I did get some advice from the upholstery man my Dad was using then.

A: I have a friend that has done several tops all GM cars with no training, self taught they all look and perform great, His advice to me be patient and save the old top for comparison and marking, get the fisher body manual has good directions, hope every thing works out well.

A: I understand AMES sells a book on this matter. So far I’ve heard about……

Fisher Body Manual AMES Conv. Top Book “Restoring Convertibles” Book (out of print ??)

Personally, I would think the critical details for such a job would be….

1. Measure carefully; recheck

2. Use the correct Tools

3. Make sure you have all required replacement components (good top, pads, tack strips, etc)

4. Let the Top stretch for a few days before hand (warm)

5. Put the Top on while its soft and warm (sunny day works best)

6. Have a friend help

7. Read all the reference material you can find; ask others who have done it.

As with any restoration project, many tasks can be done yourself if you prepare and have patience.

A: I am currently in the middle of replacing the convertible top on my 1968 Firebird.

For reference manuals I am using the 1968 Fisher Body Service Manual and How to Restore Auto Upholstery by John Martin Lee (1994 – Motorbooks International Publishers and Wholesalers)

I am installing a Crown vinyl top purchased from Classic Industries.

I purchased the pads from Ames Engineering.

I have run into one glaring problem in regards to the Fisher Body Service Manual. The manual says that you need to position the rear bow 13-3/16″ from the front of the rear bow to the center of the center bow. I carefully positioned my rear bow with spacer sticks and duct tape to the exact dimensions in the Fisher manual, installed the pads and trimmed them to the rear edge of the rear bow. Imagine my surprise when I attached the back curtain assembly to the trim stick, bolted the trim stick in place and found the top of the curtain about 2-1/2″ short of the rear bow!

Either this particular replacement top is not an exact reproduction of the original top or the dimension given for F cars in the Fisher Manual are wrong.

Anyway, I’ve purchased new pads and my plan is to mark the top, as outlined in the Fisher Manual, as to where it should line up with the rear bow; then install the top via the listing pocket and retainer; then position the rear bow in relation to the marks on the top and secure it again with the spacer sticks and duct tape.

In spite of these setbacks I think it’ll turn out all right. I try at least once to do things myself on my car. For what installers charge around here (metro Detroit) I figure I can purchase and ruin three tops in attempted installations and still come out ahead. ‘Course a professional would get it done a LOT sooner than I will but this has been a pretty leisurely paced project.

If anyone on the list has info about the missing 2-1/2″ in my dimensions I’d like to hear from you.

A: When I replaced my top I ran into the exact same situation ( I also had to buy a second set of pads ). The key to getting the rear bow correct is to locate the seam properly on the rear window, and then position the bow so that it hits the notch that is cut in the top. If you don’t get this right, the seam will pull away from the edge where the rear most weatherstripping mounts.

A: If you are going to do it yourself, here are my suggestions:

1. take lots of measurements on where your top bows are now, measure from the header and draw a picture.

2. take the old top off and keep it aside

3. take a day to clean and paint up top bows and ensure tacking strips are OK

4. wire the top bows in position measured in #1, make it strong wire and keep it tight.

5. fit the rear window loosely to the rear top bow and lower tack strip (realize it may not be permanent.

6. fit the top to rear top bow where it has its side tucks (no tacks in rear bow yet)

7. wrap front of top around front header and get a general idea of fit, depending upon how top covers rear window and fit at 1/4 glass you may have to reposition rear top bow and this means refitting rear window.

Once the rear top bow, lower tack strip and 1/4 glass fits the final step of cables and front header takes just a few minutes. My best advice is don’t be intimidated, just when things look like they will never finish(and there will be a point when it will), the last 75% goes extremely fast.

I have found that on many new tops the slide-in top bow(middle bow) has the slide-in pocket mounted in the wrong spot, do not try to position your top with it.

A: First, I do remember that there was a major difference in top quality when it came to comparing the 200 dollar (materials alone) top with the 400 or so dollar one. And since the labor to install is about the same for each (if not a bit more for the cheeper top since it does not fit as well) I strongly recomend getting the more expensive one.

Also, before doing a top replacement it is a really good idea to go ahead and do a bunch of prep work that can only be done with the top off. these jobs include:

Removing and stripping the frame, painting it fresh, fixing rustholes, installing new bushings (if you got’em) and new staple to areas, new weatherstrip, and making sure to get new padding with the new top. Once your frame is ‘restored’ it can be adjusted to fit perfectly with your windows before installing the canvas so that you end up with a perfect fit in the end. Oh yes, and if you have a ele. top- what a great time to clean and refill the pump!

And, there is that ‘packagetray’ area material that can be replaced at this time too.

So, when it comes to the labor, a good shop should be able to do it for 300-400 dollars. It really pays to have a pro do it because there are tricks to it and if you make one mistake, the top is wasted… go buy another one.

I hope this info helps a little.

A: I’ve got a 1968 350 conv. that had a severely dilapidated non-colormatching white vinyl top on it when I bought it. So the first thing I did was shop around for a new top. I also got some advice from my father-in-law who does professional-quality restoration on hot-rods and muscle cars in his spare time. He told me that despite the cost, have a professional top-installer or upholstery shop do the work. Doing it your self, even if your good, is a pain in the ass if you don’t do it all the time, and 9 times out of 10 the job will end up loose-fitting. I priced tops on the net and they varied from $250 for vinyl to $500 for canvas, and professional installation would almost double that. Despite not being originally available on the car, I had a black (original color) canvas StayFast top installed by a shop that only did convertible tops. The whole thing cost ~$850.00 installed, and I’d do it again in a second (the same place would have charged $500 for vinyl, installed). I couldn’t be happier with it. My car is a daily driver in Seattle, WA and despite the rain this winter, my interior has stayed tight and perfectly dry! Now I know that several of you are sticklers for originality, but I’ll put my canvas top next to any new vinyl and I’d bet that 9 out of 10 people on the street would say mine looks better. It really give the car a great look. Anyway, I realize opinions may vary. Good luck. Oh, and BTY, I was recommended against buying the split glass rear windows because the gasket that hold the two pieces of glass together wear out quickly, but I have no personal experience with them. Someone else on the list who has one may want to comment.

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