All that stuff I prolly knew the answer to at one time or another, but I'll answer the two I'm pretty sure about:

If you over revved a Corvair, it almost certainly would toss the fan belt; It would come slack off the back side of the crank pulley and with the twist in it to turn the corner to the fan, it would just walk right off of the idler. There was something else that was common to the over speed issue, too, and my rusty memory wants to say it had to do with the valve train - seems it was easy to float the valves.

Seems to me that a quarte inc bolt would suffice for aligning the arms on a Hurst shifter. I guess I could go take up the floor plate and find out, but I won't.