I am looking to upgrade the rear axle on my 72 to disc and wanted to know if anyone has done this using a factory axle out of a newer truck. I have already invested in a new set of 35" tires with new rims (6 lug) and want to be able to use them. I would like to get a 12bolt or 14bolt unit with a 6 lug bolt pattern and with a WMS to WMS length around 67.5" to match the front axle. The front axle has 3.73 gears in it now so I would like to get the same ratio so I can use the axle for a while until I can afford to upgrade both axles with new gears and lockers. I was also thinking about trying to pick up all the braking parts from a newer truck with hydrualic assist brakes (master cylinder, brake booster, and power steering pump) to increase the stoping power. Would these parts have any chance of working with some minor modifications or would I be better off spending my money on an after market disc brake system and just rebuild my exsisting 12bolt? It would be nice to have a rear axle that is closer in length to the front then the orginal so the rear wheels don't set in so far.