Proportioning valve ????? 68 dart/diplomat

hey on my 68 dart there is a block on the frame, is that a residule (spell check please)valve? or something else, my dart had 10"drums on front, now it has disc/drums. I know this block on the dart needs changed, and was wondering if i have to remove the factory 68 dart block, and if i do can I use a Proportioning valve from a 85 Diplomat?( i have one)
or would it be better to remove the block put the front lines together and use a adjustible P-valve, oh and I am using a disc MC..
any suggestions?
Author: admin