I bought a used CSR and it lasted about 6 or 7 years. Not sure how much use it had before I got it. Just recently bought an MSD mini. Seems to work well. Time will tell.
I have an IMI-108 Mini Starter like mentioned in that link posted above, and purchased it at Good vibrations, http://goodvibesracing.com/IMI_Starters.htm (Close to the bottome of the page). I bought it from them as that was the cheapest ($189.00) I could find that starter for and it works great!
I've been using Summit's mini starter for about 6 years now with no issues. P/N SUM-820311. I had the same hot start issue that you describe. I am even running headers now without an issue for starting.
I know that washing and waxing my car with the present condtion of my paint is like polishing a turd.....but it's my turd and I want it polished!
I'm pretty sure the solenoid spring hasn't been my difficulty before because the starter never failed to engage. Just would roll the motor either too slow or not at all. Almost like all the clearances tightened up to the point that things seemed to be froze up. The last time this happened I decided to try a little test. I ran the car up to operating temps and shut it off. Tried to restart. Barely rolled over. Dropped the starter. Dropped it in a bucket of water till it was cooled off( couple of minutes). Blew it out with some air. Reinstalled it (total time: 10 mins). Fired right up. Rolled over like a new starter. I guess the heat somehow affects the efficiency of the windings in the motor itself after time (just conjecture on my part). Probably a rebuild would fix the issue for awhile but it's probably going to be a reoccurring issue. The minis seem to last a bit longer than the stock size issue. Probably because there is more spacing for cooling air flow. Then again they better for the additional cost.
Current flow doesn't like heat. The hotter wires get the more resistance to current flow, higher ohms. I put three stock new starters in my 69 GTO and each of them dragged when hot. The gear would engage the flywheel but it wouldn't turn the crank fast enough to start. Too much resistance when hot. Not only a hot starter but the wires going to the starter as well. A stock 68 has the cable from the battery, the purple wire from the start switch and the yellow wire from the starter to the distributor. The purple and yellow wires go down the tube bolted to the back of the block to protect them from heat. If your goal is to keep the car stock looking you could try changing the wires to heavier gauge wire, may help. I put a high torque mini starter on my 68 Firebird and it works flawlessly cranking my 10.5:1 464 cubic inch engine. I also eliminated the purple and yellow wires and remove the steel tube they ran through. I have an HEI so I don't need the yellow. I installed a ford style starter relay on the right hand inner fender close to the battery and ran the starter cable from that, then put a jumper between the starter's solenoid and the starter's cable terminal. The only time the starter cable is live is when the switch is in the start position and the jumper automatically engages the solenoid. I just did a 1777 mile trip to central Alberta from the west coast, it was 105 degrees in the badlands and dinosaur valley, The starter worked as it should every time I hit the switch. The nose of the mini starters is smaller than the stock, it will not fill the hole in the bellhousing cover. I cut and shaped a piece of aluminium to cover the hole. Obviously I'm not concerned about originality under the hood. Looks pretty stock with the hood closed though.
![[Linked Image from imageshack.us]](http://imageshack.us/photo/my-images/845/turd2.png/)
