Axles-Gears-Powr-Lok setup

Your list covers the "go", but you forgot about the "whoa".
Your A body brake setup won't work with the large bolt pattern axles, even if you redrill the drums.
Easiest would be large bolt drums (and backing plates/hardware), then you won't have to mess around with different masters and proportioning valves- and as long as you've got an order going to Dr. Diff, you may as well add this to the list:
Mopar Drum Brake Assembly
I just got the BBP drum brake assy from a fellow member on this site. Should be here Thursday. I just need to buy the drums.
The Dr.Diff setup has been out of stock for a year or so. Cass did say he might have more later this year.

Thanks for that info, i did forget to mention the rear brakes were taken care of.

[SOLD] - brake kits