I wonder if the A bodies even had metereing valves, because looking at those pics it seems like one of the two ports for the front calipers on the prop. valve is plugged, one line goes to the metering valve which tees them to the front calipers.

My 75 Dart proportioning valve did not have a plug in either one of the front caliper ports, so I just connected them directly to the front calipers as was recommended to me. The brakes work great BTW, at least compared to the old 4 wheel 9" drums!

I'm confused now as to whether I'd even need a metering valve.