Engine Starter meshing issue after hard starts

So I have had countless issues with my motor swap, there seems to be light at the end of the tunnel but here we go..

308 with 11.5:1 compression, professionally built engine pulled from another car I just dropped into my '88.

Initial startup with the stock starter worked fine, it struggled to turn the engine but it worked good enough until I could get a PMGR starter delivered.

With the PMGR installed, it made a terrible grinding noise as if the starter and ring gear were not meshing properly. (Still started the car)

Took the PMGR off and out the stock back on until I could try another PMGR (figured it may be faulty)

Stock worked fine until a couple days ago when I tried to start it with 4/8 plug wires connected by accident (oops) and ended up flooding the engine causing a few hard starts and kickbacks on the starter.

All of a sudden the stock starter starts making the same grinding noise the PMGR did, as if the gears arent meshing.

I thought maybe I ruined the stock starter (probably on its way out anyway) so I put a close-to-new stock starter back on and it makes the same exact noise.

I can see the teeth on the flywheel are a bit chewed up from the Hi torque, but nothing serious. I cant imagine that would cause it not to mesh. Although, it does still start the car.

I am at a loss and really dont want to have to replace the flywheel. Everybody is telling me this issue lies on the ruined ring gear teeth.

Any help would be appreciated!!!

Thanks
 
What other car was it from and is this the flywheel and bell housing from that same car?

It is the bellhousing and flywheel from my old motor. I believe both of these are working fine with the motor application though as the starter worked perfectly fine up until a couple days ago.

Although, I noticed last night that the lower starter bolt hole is stripped out and will not tighten fully. I only noticed this just now.

Would this cause the starter to be kicking back away from the flywheel if it isnt fully tight?

I imagine it would.