Any thoughts on a square wheel setup i.e. 18x9.5 +30 running for example 255/40/18 F 265/40/18 R. Is anyone running this type of setup? And would this fit with minor modifications to the body?

 

255-40/18 in the front is huge. As is a 9.5 inch wide wheel with a 30 offset. You are not going to get that to fit in the front with what I consider minor modifications, especially if you are lowered.

a 255-35/18 gives you a much better chance of success, but you are still likely looking at rolling and pulling, plus bumper tab relocation, and adding additional negative camber.