on my project 2000/2001 dime i went with the waylayed 7" dual diaphram booster, makes alot more room and bolts right up. (i did have to weld on the eye from the stock booster to this unit, you might not have too tho). i am also doored with 14" rim /75 series rubber and i have plenty of room. hope it helps alittle man
http://www.waylayedinc.com/Waylayed2010/ww/products/Zinc-Dual-Diaphragm-Booster.html