I never fully answered your questions. I am narrowing a BJ front beam. I have been doing some research and a 6" seems to be what most people run. My only concerns would be clearance for the shock towers and if the steering box would mount correctly. I want it low, probably about as low as yours but still be able to somewhat daily drive it. I plan on sticking with stock wheels (ones with the 8 oval holes). My only problem with that is I know I will need a low profile, but I'm leaning toward whitewalls. I am not sure that the size I will need will come in a WW. Anyway, hope that answers most of it. If ya wanna help, I'd love it!