Help on shortening a Dana 60 truck housing

Thank's on the tunnel information MoparManDan! I suspected it was but I've always seen some offset where the drive line passes down the tunnel. Of course, most of my cars have usually been "less than straight" (more within my price range, lol!). But for the O.P. : What kind of truck did your 60 come out of? There's a whole list here of different variations in the truck Dana's so you can figure out a little closer what you may be up against. Good to have friends into off-road stuff, too!
https://www.pirate4x4.com/d1/tech/billavista/PDFs/Dana 60 Manual (Rea Axle).PDF