Big John,
I've been thru this very same stuff these days. It was on a 250 with a stick trans. I swapped the engine and changed the flywheel, and the one that remained in the engine was clearly worn. So the noise was no good. There was too much distance between the starter gear and the ring. So I put a washer just on the outter bolt, that makes the distance smaller. The nois went away. Tried twice before reaching the right size. If You put a spacer thru the hole starter, it will just set it even farther from the ring so it'll sound worse.
Loose the starter, remove the shims, and put a washer only in the bolt that's farther apart from the crankshaft.
Good luck
