That kit is designed for a torsion bar 2WD truck. The spindles are slightly different and the torsion keys won't work. Maxtrac has other kits for sale, and they also sell the spindles "a-la-carte"
You can buy their lift coils for $165 to make the 4" spindle lift a 6" total lift. That's what I have. You can fit 33's. Mine currently has 32's. I stuffed 35's before and they rubbed, I had to take the plastic rock guards off the rear of the front fender, and trim my bumper.
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