How do you check the starter gears (mini) to Flywheel clearance and install shims if needed if you have a scatter shield installed? No access to see anything?
I've also heard that a starter will usually engage in one of four places or areas of the Flywheel and there will be wear spots to prove that and the other areas of the flywheel will have no wear...some corrosion even as it has never meshes with the starter gear. Anyone have any thoughts on any of this? Thanks

Basically you have to try out different shim combinations until the starter gets quiet. The crudest way would be to install the starter minus shims and add shims until the starter no longer squeals while engaged. Not recommended but with a scatter shield you do what ya gotta do.

About 10 years ago I got a spec from a Chevey dealer, who photocopied it out of an old book.

Pinion to flywheel clearance (peek of the pinion tooth, valley of the flywheel tooth) is .020". Less than this requires shimming under the starter pad. A .015" shim adds about .005" clearance. Grossly over .020" requires shimming the outer bolt only. A .015" shim tightens clearance about .010".

As charbilly said, you are probably looking at trial and error with scatter shield.

Thanks guys...crude is right.