depends, if you are adding a disc \ drum combination proportioning valve, there is only one line that has to come off the drum brake distribution block. The one that goes to the rear. The two front hard lines are typically not long enough to reach the comb. prop. block, so you must use new tubing lines available in various lengths \ sizes at auto store. likewise, if you add only a proportioning valve, you still need the rear one separated and again the front hard lines are not long enough to reach the dual master, so you either extend the line with a coupling and another hard section (from the auto store). However, if you are using a dual master, none of the stock drum lines fit the master. so a lot more info is needed to answer. PM me and I can walk you thru it once you tell me what parts you are using.