A lot of A body stuff carries over. I don’t know the details on the early A body cars but a lot of the 68-72 stuff is similar, 73-75 too.
1967 was a weird year with early and late stuff. 1976 had some one year only stuff related to emission controls.
I think I got this figured though.
1972 did have a few small unique things. The plastic housings used the external ground with a tab on the outer edges of the bulb socket.
View attachment 1716490563
View attachment 1716490564
This is the only year that I have seen that has this two wire terminal to a blue colored collar. Sort of weird.
View attachment 1716490565
Looking close, there is a tab to index the collar in the socket to get the bulb to make contact with the “contacts”.
View attachment 1716490566
If that collar is out of position, the bulb’s contacts won’t touch, no light. There are three indentations, two are for the pins on the side of the bulb housing, one is to index the collar.
View attachment 1716490569
I did have power to the wires.
View attachment 1716490567
View attachment 1716490568
The inside of the socket was cleaned with a Scotch Brite, the collar was put in properly and….
View attachment 1716490570
View attachment 1716490571
View attachment 1716490572
Now onto dealing with the dead gauge lights.
That is usually the headlight switch, right ?