Step back and look at the car just like it is in the photo. Look at the gap at the top rear of the door -- the gap to the quarter panel. Use a stack of corrugated cardboard squares for a measuring device and see how many pieces fit the gap. Do the same on each corner of the door.

Both gaps on the hinge side should be the same. Both gaps on the latch side should be the same.

Do the same on the other side of the car.

If you find that on one or both sides that the bottom gap is wider, particularly at the rear, your car is suffering from a case of belly sag. Belly sag is indicative of weak structure. These convertible bodies were not modified very much to accept the additional weight and loads imparted by removing the roof structure. If compromised by collision or rust damage they can easily become unsafe to drive far sooner than a comparably rusted on bottom coupe.

Look at the pinch welds, the long seams on the bottom where the floor flange is spot welded to the rocker flange. All three layers of steel should be in good condition with no rust.

Look at the floor pan where the front of the rear springs bolt on. Take a screwdriver and jab the floor from the bottom. It should not make an indent.

Look at the rear frame rails where the rear shackles attach.

And look at the floors from inside, with the interior and carpet out.