I have seen a couple threads thru the years with full frame disassemby for powder coat, the reasoning from what i gathered was to stop rust 100% but maybe there are other reasons i don't recall. just remember the factory uses Jigs to align the rails and position the cross members so take precautions, I like the idea of removing one rivet at a time and pre drill the hole to match the new bolt size, tighten the bolt and move to the next ect, then once all are drilled go ahead and dissemble..
Here's one:
http://67-72chevytrucks.com/vboard/s...d.php?t=645614
good read:
http://67-72chevytrucks.com/vboard/s...assemble+frame
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