My .02, stick with the torsion bars. I have a '68 with the front sway bar, also the same bar in my '82 (Front sway bars were all the same from '63 thru '87. While I've not done the actual install yet, I took a spare bar, and the mounting brackets that attach to the frame, and mocked up an installation with the later stock sway bar. Looks like all that will be necessary (aside from drilling the holes) will be a small bit of trimming on the top edge of the frame to bar brackets. If you can find a later truck with sway bar to park next to yours and compare, you'll see it appears to be a pretty straitforward mod.
