Tony already knows this, he just didn't elude to it. If the rear was narrowed, more than likely mini-tubs would also have to put in....maybe even some cut & weld on the frame, depending. He just didn't post that part.
Offset has nothing to do with making a wider wheel fit in terms of where he is at now, because not only is he really close to the outer fenderlip...he is also close to the inner fenderwell, et al as well.
I would assume he is just looking to see if anyone else has done it yet, to see what all was involved (what they did) for this particular application. I'm right there with him in this quest for knowledge...lol