I have a set of Firestone air bags on my 06' Dodge ram crew cab. Without them the truck had so much wobble I couldn't get over 55 mph. With the bags ( which are set up so I adjust individually ) I cant tell there is a trailer behind it.
yea, you would have to change backing plate, shoes & drums along with axles. but that's a lot less work IMHO than a rear end swap in a driveway. I would be willing to bet the axles themselves are the same diameter.
that rear is what I have in my Ramcharger. technically just a 9 1/4, just HD version. You could just get the axles and slide in your rearend. I replaced my welded spiders with a set off ebay for a standard 9 1/4..
just FYI, you can remove the dash without removing the windshield. You have to pry up the windshield rubber and find the screw heads. After finding them you use a chisel point on an exacto knife & just notch the rubber. ive done that a few times with great success..