NSS / backup lights question
You should remove the '71 diagram. Not only is it different from your 65, it REALLY screwed up the display. What 65Dartman posted earlier is essentially correct............
This now should be wired (in the 65) more like a 4 speed switch........coming through the bulkhead.
Hang on, I'll see if I can post some of the diagram................
65 factory manual........
[ame="https://www.dropbox.com/s/upks33txhbe9tjw/1965%20Plymouth%20Service%20Manual.pdf"]https://www.dropbox.com/s/upks33txhbe9tjw/1965%20Plymouth%20Service%20Manual.pdf[/ame]
The engine bay wiring is page 8-109. Find the "back up lamp switch" at far right middle of page, wire B1 and B2 go from the switch back to the bulkhead connector, position 6 and 7 These are both shown (chart to the right) as black with white tracer. These of course you would have to have added for the new style automatic switch.
Now go to page 8-96, the inst. panel wiring. Wire B2 comes in from position 6 of the bulkhead connector, goes down, off the page and continues on the page below. On page 8-97 B2 comes back on the page at the very bottom, goes over and connects to the kick panel connector and feeds on back to the rear lamps. The switch shown there of course is your original automatic switch on the column. If you go to the color chart at top left of 8-96, you see that "B2" is violet.
Now, we go to position 7 of the bulkhead, page 8-96, and wire B1 (B1, B2, by the way are shown dotted because these only exist in factory form for stick cars) so follow that off the page, down to the bottom of page 8-97 and you find it goes to terminal "B" of the wiper switch. Now these vary some over the years but generally, "B" is going to be a brass strap which jumpers over to V1 on the switch, possibly with a circuit breaker there on the switch. Now follow V1 up, off the page, and find it again at far right, middle of page 8-96, and you'll find it JUNCTIONS with the flasher and other wiring. Follow from that junction "Q2A" up the page and you'll find it goes to the fuse panel
Here's the 65 diagrams from MyMopar.............and I see they really don't document the 4 speed switch........
http://www.mymopar.com/downloads/1965/65ValiantBarracudaA.jpg
http://www.mymopar.com/downloads/1965/65ValiantBarracudaB.jpg