67 Dart brake change

What do you think of this proportioning valve? It's a KH Disc brake proportioning valve for 11" front disc brakes with 11" X 2.5" drums in the rear. This was from a 1978 pickup. And here is a photo of a new master cylinder that I would use as a replacement. What do you think of that? Am I heading in the right direction? Short of going to the junk yard and looking for the parts (which I would love to do, in warmer weather) , but I might think it would be rather hard to find some decent parts around here. Thanks guys. Do appreciate the help.

MC will work as long as it will bolt up to the firewall and has the correct cup for the brake pedal rod. Make sure you put the grommet on the rod so it doesn't come out (Safety). The Prop vale is iffy. They are normally set up according to vehicle weight and weight ratio front to rear so you may get rear wheel lock with it. Go to your Chrysler dealer and get one for a mid 70's A-body. They are still available. Just got one about 4 months ago. Naturally you will have to be lucky enough to find a parts guy willing to look thru a real printed parts manual for the part number.....

Larry