I have installed a 4" spindle lift. With trimming you can fit a 33s. You cannot use a rim wider than 8" or a backspacing less than 3.5" (offset more than -1/2" or -12mm). If I were you, I would see about installing a subframe kit. There may be a few 7.5" fabtech kits still out there, and I know BDS made a 6" kit. The spindles are awesome, but you will only want to go higher.
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