57,
I don't know of any of these kit suppliers that will tell you what parts they put into a kit. Once you know you don't need them anymore. The six lug kit is available from a variety of vendors, most use a 12" rotor and calipers from probably 73-87 van or 4X4. They recommend using your existing hub and changing over to timken bearings. This kit can get fairly pricy and generally will not work with stock wheels.
I used the 5 lug conversion. I was fortunate to obtain the 11" rotors, calipers, & hoses from a 74 Malibu donor car, bought a bracket kit and bolted them right on. I had a machinist re-drill the rear axles to match the car bolt pattern. Either way you have to buy wheels, might as well get something more common. I also had the stock hubcaps modified to fit the aftermarket wheels.
Fred
