1975 Plymouth duster brake relay question?

That's what the wiring harness looks like if you unwrap it. That's been unwrapped so I can trace down wiring and find out where things go. Kind of like that when I got it but everything works and it runs. I was just questioning that relay. I didn't think the outside wire by itself went from that relay down to the proportioning valve. So where it came out of the number m spot on the middle bulkhead connector that goes to the dash brake light. I just tied on to that and ran it down to the switch on the proportion valve. I left everything else. Stay the same on the relay