Hood light?

I have it it’s just a little hard to piece it together.
I don't know what you are looking at that is hard to piece together.
When we say Factory Shop Manual, we mean the books that say Dodge or Plymouth Chassis Service, and Body Service.

Let's look at '72.
On page 8-144 there is a general key to the diagrams
1704202401827.png

Now the part you are curious about has a plastic housing two contacts for the bulb base, and I can't see but maybe a side contact for bulb?
It looks like 3 wires into a fat T shapoed connector. We know its engine compartment.
Lets find lamps and connectors on the diagram.
1704202824906.png

We think its a lamp so the only ones shown are in the front.
1704203230264.png

And lets focus on the connectors that look like they are similar to the one in the photo.
1704203688531.png
The coding is like this:
First part of the code is the circuit. L is lights, D is turn signals.
Next part is the circuit and wire segment L6A is Light circuit 6 segment A
After the dash is wire gage and colors. 18BK/Y* is 18 gage Black with yellow trace.
If it helps, in MS Paint or similar simple program colorize the circuit of interest and erase the others as needed.
1704204243874.png


I wonder if anyone has labeled a whole harness before.
Yes.
People have laid out harnesses on the workbench or plywood and labled connectors etc with masking tape or writing on the board.
Its a good way to do repairs.

Harness illustrations are in the assembly drawings. Unfortunately I do not see a 1972 for sale. Closest Faxon has for sale is 1971 A-body.
https://www.faxonautoliterature.com...t-Electrical-and-Body-Assembly-Manual-ReprintIf you think it may be helpful then maybe its worth it. By '73 there were noticible differences in wiring from '71. I think 73 and 74 are similar, 75 and 76 are each pretty unique.

This is what the 67-9 Instrument panel electrical assembly drawings look like in Faxon's reprints
https://www.forabodiesonly.com/mopar/threads/light-group-wiring-harness.542512/post-1974333448
https://www.forabodiesonly.com/mopar/threads/m-h-wiring-harnesses.514037/post-1973847888