I helped a friend put power on a 54 useing a 4x4 gm box and had clearence problems with the left front tire and draglink. The 46 would be even closer and would probably even have to hack up the grill and fender to clear the box. The power rack looked like a good option mounted just behind the core support crossmember with the steering arms from the spindles flipped over and turned forward. The rack I have came from a 01 or so 3/4 ton pickup. Hooking up the column with some d shaft and a ujoint or two would be no big deal.

ttodd's toys