Hi Jim,
Thanks for the offer. My goal of this effort is to figure out if we can retrofit the old rear ends with modern, readily available, off the shelf drum parts without needing any customization.
My curiosity got the best of me and I ordered a variety of brake parts. I've been playing with different parts from 1990's 3/4 and 1Tons and might have actually found a solution!

I'm still waiting on a couple more pieces but I'll post an update soon. If it works, I'm going to do a video and list all the part numbers out.
Thanks again for the offer, I may take you up on it if this retrofit craziness doesn't pan out.