Proportioning valve question

Let me make a suggestion. About 15 years ago, I installed a front disk brake kit in my 69 Barracuda. It came with an adjustable proportioning valve. It has a knob on the bottom that could be turned to vary front to rear pressure ratio. It works really well. As I remember, the brake lines fit pretty well. You could install one of those now. If you switch to disk brakes, you'll need a proportioning valve anyway.