my 71 Malibu had 4 wheel drum brakes from the factory with no proportioning valve but it does have a junction block or splitter mounted on the driver's side framerail under the firewall. my question is now that i have converted to disc brakes with a proportioning valve do i still need to leave the factory junction block on it, or i guess what i'm really wanting to know is can i still leave it on the car and will it have any ill effects if i do leave it on the car? any input is appreciated. it is a manual MC if that makes any difference.