Don't know if you are still looking for information on your Centurion or not but if you go to
http://clubs.yahoo.com/clubs/centurionconversions
there is a group of us that may be able to supply you with just about any info you need. Sorry to hear about the transfer case,had the same thing happen to my 1 ton Centurion's Sterling 10.25 rear axle Jan. 2001.
Turned out that Jiffy Lube didn't check the fluid. They paid for the fix though.