Trim it a little, beat the floorboards back JUST A LITTLE, and skip the body lift.
I know it's a well accepted method of fitting a little bit bigger tire, and moving your rockers a little bit further away from damage... but..
it might just be me, and no offense to those with body lifts.... but....
yuck. I just can't do it. I really hate the look of body lifts. All that frame showing, and no ground clearance gained, and center of gravity raised.. (I know, I know, you guys with body lifts have never had a problem with that and all...) Shifters sitting lower, or extended, geometries changed.. I know I sound like a broken record, and I am mostly a trail guy, I do drive my "turtle" on the street, but I certainly don't care about dents and trail rash, or trimmed fenders, etc... but, did I mention I hate body lifts??
Since you have a rusted buggy anway, skip the body lift, and do a little trimming. Do you think my green Kick looks horrible with the trimming I did? I am certainly no body man, but I think it looks just fine for a trail rig, and with a little more care, and some fender flares, it would look pretty freaking nice done this way/..
I guess my point is, why get a body lift when you don't really need one? 31's will fit without one, so... what is the benefit of screwing around with a body lift, when you don't need one, and they especially since they don't really add any function or advantage that isn't more easily accomplished with a little trimming, and rocker/rock slider innovation. There are several methods that looks good, to protect your rocker areas, that don't require a body lift, and don't detract from ground clearance and breakover angles.
The only time I would consider a body lift is if I had a mint vehicle that I wanted to put big tires on without trimming... uh.. oh yeah.. what point is there in putting big tires on something you aren't going to take off road? So, in other words, I don't think I would ever put a body lift on anything, as it doesn't add anything to trail riding, and detracts plenty, in my opinon.. but then again, I am a hard head, and not too politically correct.