Thanks for the replies. My question as to pinion shims was whether to add a .010" shim to my original 2 shims which already add up to .039". I got my hands on the GM Rear Axle Overhaul Manual and it says that my '46 would have room for .024"--.042". The Manual also says if replacing the pinion to start with .033" of shims so I guess I'll start there. Having some fun now.
