I have a 73 Dodge Challenger and I am installing 4 wheel disc brakes. I just want to make sure before I buy these. I think I need a drum distribution block, not a proportioning valve. Does anyone have a part number or brand. A dealer says they have the correct part, I just want to be absolutely sure. Thanks everybody.

I am assuming you want a 4 wheel drum splitter with the electrical switch for the brake warning light? EDIT If so I'd think a 67 up 4 wheel drum splitter would be what you need (I'm thinking they added the warning light the same model year as the dual bowl which was 67)

check this out, probably what you need

http://www.summitracing.com/parts/wil-260-11179/overview/

Al, just go down to any good auto supply shop and get two of these. Get a 3/16 plug for the one to the rear brakes. Having two separate circuits (front/rear) makes it easier to plumb and tighten the brake line fittings. I've built many brake systems and trying to get a 3/16 brake line wrench to tighten a 5 port dist block is not fun. While you're there get a few extra plugs in case you want to test the master cylinder.