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1973 Transmission wiring?
Swapped a 466 motor and Toploader into my 1973 fastback which was originally equipped with 351c and a floor shifted automatic.  Problem is that was many years ago and I had not quite finished and finally now working on it again, but not sure what some wires hanging below firewall down by bellhousing are for.

There are two plugs each with two wires.

One has a round rubber end female parallel double spade connection attached by black and brown wires. I am guessing this was backup light plug for the automatic transmission. Don't think my Toploader has a provision for that, so how to get backup lights working?

The other separate pair of wires are brown and green and whatever connector it had has been cut off. So, just the 2 wires hanging down there.  Are those the two wires that would have been attached to the neutral/park safety switch on the automatic transmission or floor shift? 

Tranny and shifter are both long gone, but I just found a pair of similar colored wires attached to a hard plastic round end having another female double spade connection, but with the two spade slots set in a "T" formation instead of parallel to one another.

Seems likely more than a coincidence that a shelf with leftover or uninstalled parts mostly for Mustang would have a plug and wires laying there that look a lot like those cut off under car...

If they are for neutral safety switch, then I can either solder them together and have start possible in or out of gear like the old days, or rig up a switch to my clutch pedal so starter circuit only completes when clutch is pushed in like modern stick cars?
[+] 1 user Likes brushwolf's post
Manual cars had a harness that plugged into a 4 pin connector. One pair (red w blue stripe) was looped for the starter circuit. No such thing as a clutch safety switch in 73 Mustangs. The other pair went to the backup light switch. The switch mounted to the rear of the shifter body. You can make your own from an old auto NSS.

Similar, but different year:  


[Image: shift_assembly.jpg]

Thanks! Didn't see the image first time I looked at your reply. Switch looks kind of like some old brake light switches too.. Have to see if I can find automatic shifter I took out of the car and see if NSS is still on it.
I fabricated my own wiring for the back-up lights as HemiKiller stated. You can buy the harness from our favorite vendor Ohio Mustang Supply or possibly one of the others, if they have it available.......
Thanks, Jay
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