Not sure about the different offsets on rotors,
but I've heard of a couple guys using around
1990 or so 8 lug 4wd rotors for this. I was
contemplating this retrofit myself on my 52 3/4 ton but ended up getting a 1/2 ton front axle and a 6 lug disc brake kit. Also got a 1955 1/2 ton rear axle. (to match the 6 lug front hubs)
The spring perches on the 55 axle have the same
spacing as the original rear, so no cutting and welding is required.
