I have an 85 Chevy 12 ton pickup with a motor out of what you think is a 73 Chevy but the starter grinds are there two different size of fly wheels for a Chevy 350 in any year?

Did you use the starter from the 85 model engine?? If you did then it is the wrong one for the early model engine, And you will need to get a starter for a 77 model engine, and it may still need to be shimed. And yes GM did make 2 different fly-wheels but that is not your problem.