8 3/4 pinion shim question

I am reusing the same gears, but I think this rear end has been taken apart at some point. There was no shim under the inner bearing, so I don't have anything to reuse, and it looked like the only shim that used to be in it was on the front side and it broke, because I took it out in pieces. I used marking compound with the old bearing and it looked like it was too shallow without any shims, hence the .040" to get it right, but I didn't know if the new bearing would compress some to the old bearing dimensions once it had been run for a bit or if the old bearing had been really abused and should never have compressed like that to begin with.