How would you recommend cutting the rivets and separating the two halves? How would you recommend securing the new back half? What type of fastener?
I've done alot of ranger rivets, not just the frame swaps, also done plenty of hanger and shock removal as well as spare tire holders.
I've used both a torch and an 4.5" angle grinder.
Grinding (or cutting rather) is actually way faster and much cleaner than torching.
Use the 1/8" cutting wheels, and cut an asterik * pattern into it on the tops, then cut in from the sides to knock off the little triangles. You may need to use a 1/4" thick disc to smooth it down flush, the rivet will pop right out with minimal force using a punch and hammer, provided you ground it flush/more than flush. (Don't use harbor freight wheels, they just disintegrate at a faster rate than they cut, use dewalt xp wheels or other quality disc brand.)
You will see the perfect circle of the rivet body crack through once the button head is 100% gone. If you don't see the circle outline completely keep grinding. It looks like when sheetrock or bondo crack, it's still there and complete, but you can see the outline.
I can take all 16 rivets (8 small, 8 large) and pull the rear frame off with a grinder in under 15 minutes. It's not the big hassle people make it out to be if you are familiar with using a grinder properly.
Do not just take a 1/4" grinding disc flat to the whole head down from the start that will take forever. Cut as much material out first as it only takes seconds.
I use grade 8 cadmium plated bolts with nylock nuts and hardened washers to reassemble. One of the trucks I've done a frame swap to is still on the road with 300k miles and done back in 2001 and been used for towing and hauling firewood. No problems.
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