Another post restoration issue cropping up on my 71 442. A few weeks ago, while driving, the fuse to the directional signals/back up lights blew which also took out my power windows, as the ignition feed for the relay is beside that fuse. I replaced the fuse and there hasn't been any issues until today when I turned the engine over and then later realized my back up lights weren't working. It was the fuse again which I then replaced and now it has progressed to the point the fuse blows as soon as I turn on the ignition. Understanding electrical circuits and reading those wiring diagrams isn't my forte.
Can someone advise if there is an area in these circuits that would be suspect on original wiring? Weak points? Can someone also let me know what's included in this circuit, so I am able to disconnect those items and add back one at a time to see which wire is responsible. To immediately blow like it is, without using the back up lights or the directional signals would mean there is an exposed wire touching metal somewhere in a related circuit, yes, no? All ideas to help appreciated.

 

Update: I traced the wiring and noted it goes out to the vacuum switch on the intake, new for 71, and noted the two little wires going into the plug on top were touching. I separated them and problem fixed. It came back to me last night that I had this same issue on my 71 SX about twenty years ago.
I thought I would pass this along for reference in case other 71/72 owners had this problem.