Look in the AC/ heat section of the factory service manual. You can download 'em free at MyMopar.com Some of them there are due to the efforts of guys on here
Thanks 273 you posted a couple of wiring diagrams for 73+71 darts that helped a lot. I've got 3 vacuum hose sets all the same. Going thru some old posts some water valves were spring loaded.That would solve everything.