I've seen 1 or 2 people comment about fitting 37s on stock suspension/wheels with just a minimal amount of trimming, there is an older thread somewhere about it. I'll see if I can find it.
For the comment about rubbing offroad, I know this is a dumb question considering the trucks intended purpose, but when you say it will rub offroad, are you talking about high speed offroad, jumps, etc (trucks intended design) or it will rub even with slower, trail driving (not really rock climbing, more like getting to the hunting area, exploring remote camping areas, etc). My use is the second one, no high speed offroad and probably rarely if ever near full tuck on the trails I have access to and definitely not in the mall parking lot lol