If you only changed the pinion bearing you should start with the same thickness shim (s) that you removed. Install the retainer, with gasket if you have one, then install the yoke. Get your back-lash adjusted then check your gear mesh pattern. If it's not correct you'll need to remove the pinion assembly and either add or remove shims to set pinion depth, re-intall, set back-lash, check mesh pattern.....etc. Others have said that they have successfully used silicone in place of the paper gasket

Here's a link to a shop manual, check out the section 4-16, Rear Axle. Good guidance on major repair.

http://chevy.oldcarmanualproject.com/shop/1954truck/index.html


Here's a couple files that might help?
Attachments
Illlustration.pdf (400.48 KB, 1 downloads)
Another diagram
Differential Gaskets NOS.jpg (39.85 KB, 140 downloads)
Gaskets for Retainer

Ron - - Dusty53
1954 Chevy 3604
In the Gallery Forum
"You can't dance with the Devil and then wonder why you're still in Hell."
"They will forget what you've said, and they will forget what you have done but they will never forget the way you made them feel."