Joe's is done on the factory crossmember. I did mine the exact way that he did his. If you ask him im sure he would post up the pictures on how he did his. It's all just beefed up with a couple pieces of flat stock.
91 yj, 4.0, AX15, SOA, 8.8 rear, 4.88 gears, 2.5 inch springs front, m.o.r.e shackle reversal, m.o.r.e shock hoops, 3 inch springs in rear, bilstein 5150's, shock bar, m.o.r.e traction bar, lockers, m.o.r.e high steer, SYE, old school bronco cv shaft, tube fenders, 36 inch tsl's