Will a 2000 Chevy 3500 rear end interchange with a 2010 Chevy 3500 single axle rear end? Would like to make my 2010 a duelly. Thank you.

my advice to you is to get 2 rear ends side by side on the deck and compare the rear ends for major differences, check out a Chevy automobile club and ask if its been done before, or take your automobile to your local shop and get a qualified technician to diagnose your malfunctioning rear end

Possibly, compare the brakes. You will also need a dually bed.

You can put Caddy in a Ford. You can do any thing as long as they bolt up or make a adapter.