Has anyone played with the idea of putting a larger sway bar on the rear?
Yes - the idea has been played with. Every time Nay say's the truck will get out of control if you let the front flex, myself or someone else says you can control it with swaybars, either heavy duty, or advanced torsion bar style.
I thought Slee said he had them, but I may have misunderstood, can't find on his site.
MAF offers them, or at least did,
Sway Bars
I still lean toward the anti-rock style -
Currie Enterprises CJ Axle Parts
Just don't think anyone has tried it on a 80, or if they have they haven't shared. With the multiple mount points on the arms, you could tune it, or swap mount points for road and off-road to make it tighter or looser as needed.
It can be done cheap-o w/ torsion bars form the front of a Taco - or so I've heard.
the video is pretty interesting
http://www.currieenterprises.com/cestore/antirock.aspx