I have a 7 litre, single MC and want to change it over to a dual. I have read all the posts but they all seem to talk about drum to disc or drum to drum or non power to power drum. I have power disc already drums in back and just want to change over to the dual MC. I have a cylindrical brake something under the car connected to the rear brake lines. I think this is a proportioning valve. Does anyone know, it says Kelsey Hayes on it plus a part number. So here is my real question, do I just need to run the dual rear brake lines into this KH device and then to the rear brakes, and then run the front brakes into the junction block (brass) that is already there. If anyone knows please let me know.