rdbates, If you are talking about a 350-24, your truck has a hydrovac. The master cylinder with the vacum from the engine is what applies the pressure to a slave cylinder mounted on the hydrovac and that in turn applies pressure to the wheel cylinders. There is more going on then that but thats the short version. If it can be done (I don't think so) you would have to have a dual slave cylinder on the hydrovac. My 55/2nd has the same setup. Get a copy of maintenance manual x-5303 and check out how the system works. Got mine from Gregs Automotive at www.gregsonline.com Dave