Well, I am a layman to start with...

I have a 78' Chevy C-10 4x2, 454 auto & 400 trany. The
starter spinned the first time in 1996 and I replaced it with a
rebuilt starter; worn out quick and I got another one with
the warrenty... same problem... so I had Grand Auto looked at
it and replaced the flexplate. (168 teeth; external balanced)
(he didn't put it reversed)

For many years now, I keep replacing starters (AC 323-255 or
Bosch SR518X)... shimming, grinding, ... piss me off

Now, I need to drive this pickup since my car is dead. Finally,
I went under and looked at the alignment. Bingo, it's exactly
as you guys described. The bandix throw is too short. About
3/16' short thru the ring gear on the flexplate.

HELP!!! What's the final solution for this thread?? What
starter have you found matched with 323-255 and with
a longer throw?

Can I grind off the stop washer on the starter so the throw
can extend further?

Thanks so much!

Tom