Rear end swap? 89 4x4 3/4 ton to 71 K10

[franken]

Hey,
I've been trolling CL and ebay for a round pattern NP205 for quite a while and recently added NV4500 to the search. Up came an 89 Suburban 3/4 ton that the owner had converted to an NV4500/NP205 using an AA bellhousing.

I bought it since the price was less than the cost of a 205 and parts to make a clutch work would be more than the truck.

The not so original plan is snag all the bits off the Sub I want, part the rest and hopefully get the scrappers to drag the rest off and give me a few bucks.

Patient: 71 K10. Obviously 6 lug wheels
Doner: 89 4x4 3/4 ton w/ 14B SF rear. I think the front looked like a D44. Of course, 8 lug wheels.

Anyway, as I understand it, the front diff will bolt in, but the rear has wider spring pads.

Since the frames are similar widths, it must be the brackets on the frame that make the distance between the springs wider. Since I have the truck, I can grind or torch off the rivets and put the brackets, longer springs and finally the diff on the 71.

The deal also came with a 14B FF rear that I forgot about and hope to pick up tomorow. Not sure of the pad width on it, but it seems some had the same width as my 71.

I'd like the 3/4 ton suspension and heavier duty diffs.

Another option is putting the 71 body on the Suburban frame. Remember that Suburbans in 89 still had the 73-87 square body style. I've rolled around under both trucks and the body mounds seem fairly similar. Searches say the core support brackets need reworked, but that seems pretty doable. Wheelbases are different so it seems the rear diff would have to be moved regardless.

So the questions are (finally):

Should I just not bother with the diff swap and stick with the half ton stuff? Since a truck w/o axles won't roll this would be easiest for the scrappers. Any chance HF castors will support the frame and shell of a square sub long enough to drag it on a rollback?

Should I get the spring pads moved on the 14B SF, or use the brackets from the 89, drill new holes, and bolt them on (since I obviously can't do rivets like the factory)?

Or, should I swap bodies?

I have tools, air toys, air system, and the compressor to run it, OA torch, cherry picker, etc. so all I lack is ambition...

Sorry for the long and rambling first post... I'm pretty thick skinned so yell at me if needed. I did search and have spent hours reading up on the subject.

Advice?