Firestone Ride-rite, anybody have?

[zakt]

I will be putting a 3500lb camper in the back of my truck anyone use the firestone ride-rite kit... looks like they need 7.5 inch gap from the tire sidewall to the frame, will this be possible on my 72' F350 (D70) with 35x12.5R18 (18x10) wheels?? I will have the 4" high boy blocks and skyjacker 4" lift springs so what 8" higher than the stock 2wd....Thoughts??

Thanx,
Todd