Changing to BBP on 83/4

Call Cass (Doctor Diff - http://www.doctordiff.com ) and get him to make the axles for you. He can make them any length depending on bearing choice and center section (with or without thrust spacers,thrust block,etc). My guess is that if you are still using tapered adjustable bearings on the axles, then you have the center spacer(s), or thrust buttons, in the diff because this is what the axles butt against for correct end play. There are several threads regarding the thrust block/spacers and using "green bearings" vs. the tapered adjustable bearings. Moser Engineering's BBP "A body" axles with green type bearings are too long to be used with the diff spacers installed, and then you get unwanted side load on the bearing, which will prematurely kill them. You could carefull remove the bearing adjuster off your current passenger axle and then have new tapered bearings put on your new BBP axles if you want to stay with the adjustable bearings, this will allow you to leave the diff alone (spacers stay inside).

Brakes can be any 10x2.5" from any mopar with BBP. I got the backing plates for mine off an '89 Dakota that had an 8 1/4" rear and the drums + internals off an 85 Chrysler 5th Ave that had a 7 1/4". Cordoba, Aspen, etc will all work. You will need the backing plates, internal junk and the drums. IMO the 11x3 rear brakes are too heavy and not needed.

This is right. I'm having Cass make up a set of axles for me right now that'll bolt right in using the stock brakes all except for the drums which I can re-drill. He even said they'd work without removing the thrust pins.