Setting up gm 10 bolt HELP!!!

[Wiseco"3]

I've got a GM 8.5 10 bolt in my 84 short bed. I bought a Detroit tru tru trac diff. And a summit racing ring and pinion, I've got a tool to check pinion depth but it's a pain in the ARSE!! With that being said I've read on some other forums that guys who set rears up put factory shim back on and check gear pattern. If the gear pattern is good and pinion pre load is set as well as back lash it should be fine right ? Thanks in advance for the help