I mounted my spare between the rear axle and the fresh water tank. I put a cross on top of frame rail , then I mounted to the cross piece a 12v cable winch and two long 3/4" bolts. Then I made a plate that fit across rim ( rim center, mounting holes ) That plate has a hook for the cable to hook in and two holes in the plate so when the wheel is pulled up the two long bolts go through the plate then I put on lock washers and nuts to secure the to the frame. The winch switch is mounted in behind the LP tank door . It has been there for 50000 miles