454/ 427 BB Starter Grinding/ Alignment issues???

What's up guys? New to the forum.
Bought a Hot Rod a few years ago that was mostly built and used it as my daily for a while. It's a '58 Ford F100 with Camaro clip and 427 Chevy motor (75 ish 454 truck block). 700R4 Tranny. Started eating starters a while back. Mostly alignment issues, I think???
Anyway, replaced the flexplate (broken tooth) and was about to bolt on a Mini High Torque starter but then noticed that the outer-most starter mount portion of the block was cracked and falling away from the block. So re-installed the O'Reilys starter I bought for it and just parked the truck.
I know I have a few things to fix here, but the main concern is that the current huge starter in there is only matching up to the flywheel gear halfway. That is to say that the bendix has wear marks on the front half of the gear and the flywheel is only wearing on the back half. It's like the Bendix isn't making full contact with the flexplate. The trouble is that the starter has no adjustment front to back. Only up and down.
Any ideas why the starter isn't matching up? Doesn't grind all the time. Only on occassion and with 20 or 30 people watching. Hahaha.

Gotta have both of those starter bolts holding tight. With the one hole broken out it lets the sarter move sideways from the torque. Also a lot of those had a L shaped brace/bracket that bolted to the end of the starter to the block.

Yeah, the broken portion happened after a buddy broke off a starter bolt in the hole. He drilled it out and tapped the hole, but might have drilled at an angle or torqued it too tight to cause the crack. But even with that starter bolted tight (couldn't shake it at all) it still starts to grind after a little while.

Starter brace on the back of the starter to the block-- do you have it?
It keeps the starter from twisting due to torque

also you need to be using starter specific bolts as they have a knurled section to insure positive correct alihnment

If the block is cracked the starter will not line up properly................