The 120 brakes will fit with some modifications. If you have a welder, grinder,drill and patients you can have a good clean job with single circut or dual circut disc brake conversion. You need to have the rotors, calipers and caliper mounting plates, backing plates or some call (dust covers) and the bolts that mount the caliper to the mounting plate. If I remember right one of the bolt holes in the mounting plate will line up on your original spindles. Weld up the other holes in the mounting plate so they can be drilled to match your existing spindle holes. You have to drill the backing plate holes to match. The shocks need to be moved to the front to clear the brake calipers. The bottom shock mounting bolt will need to be angled inward because of clearance issues. I have heard you can use 240 calipers. There is a lot of info here on the board about this. Belinda has a really good conversion explaining with pictures in the photo section. Hope this helps. Larry