I have an '86, and just did the same mod. I put on 33x12.50x15 general grabbers. I didn't trip the fenders, and have no lift. I was worried about rubbing too, heck when i saw the tires sitting next to the truck, I didn't think they would even go on. I took it out twice since the mod, and they rubbed in both the front (when i flexed and turned at the same time) and in the back when i stuffed the wheel real hard. I have never disconnected my sway bars, and my shocks are pretty much shot. In short, you will rub some, but nothing that hurt anything. Terrible noise to hear though. Good luck.
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