What size tire are you running or want to run ? You can fit 245/70 with out changing a thing.
Im not a big fan of air bags off road. Too many things to go wrong offroad
. Just make sure your equip is tough, wrap the air lines in Kevlar, built a box for the compressor .... the week spot will be the bags them selves. Bushes & tree stumps are deadly offroad.
Build it right or built it twice ...