Appropriate Wheel Offset for 18" Wheels?

Well we made some relief cuts and used a neumatic tool in the rear to push the fender out. I actually ended up with almost 14 inches from fender lip to leaf spring. I was going to try some 19x11 wheels with 305/30/19 Hankooks next in back. In the front the mods were much more mild, just the neumatic tool with no relief cuts, rolled the lips, and modded the rear of the wheel opening an inch. This picture is early, it actually looks pretty good now...

Sneaky, and very clever. I like that its subtle.
Nice work!