Topic: Automatic Transmission Wiring Conversion to 4 Speed

[GlennG]

I thought I would check with the wiring gurus on this one.  I am in the slow process of getting my '66 Shelby running for the first time.  My car originally had an automatic, but it was replaced many years ago with a 4 speed.  For right now, I am going to keep the 4 speed in the car.  The wiring throughout was a mess.  I have fixed most of the spllces, cuts, etc. and have now gotten to some wires that I am pretty sure had to do with the original automatic transmission.  My questions are as follows:

Could someone please look at my attached pictures as I have these questions:
1) Picture 1A and 1- have I labeled these wires correctly?  Neutral switch bypass; automatic tranny harness?
2) Picture 2 - Automatic tranny neutral switch bypass?

What was the possible purpose of someone using a bypass on these wires?  Can I disconnect the home-made bypasses in the engine compartment and under the dash, or would it be best to leave them so that I can run this car for now with a 4 speed transmission?

Thanks for your help!

[midlife]

You've got 1 and 1A labeled correctly.  The Previous owner did not realize that one can easily jumper the NSS by removing that entire harness and disconnecting it from the main underdash harness just behind the firewall plug in the passenger compartment.  Simply connect the red/blue male and female plugs there, which is how a 4-speed manual wiring system is set-up from the factory.

Picture 2 has a repaired system for the dash lamps.  Originally, there was a three prong red plug with blue/red wires, but the red plug was replaced with an ACC yellow plug.  The male bullet blue/red wire may be a console or PRDNL lamp wire, more probably the former.  It could also be a rally pac clock wire.

[GlennG]

Thanks Midlife, I do really appreciate your quick response and your expertise

[jwc66k]

Can I disconnect the home-made bypasses in the engine compartment and under the dash, or would it be best to leave them so that I can run this car for now with a 4 speed transmission?

The four speed wiring (as well as the three speed MT) for the back-up lights run from under the dash on the left hand side above the fuse block, across the dash behind the instrument cluster then, inside the car, down the right side of the shifter to a hole in the transmission tunnel to the transmission mounted switch. There is a feed thru grommet at the hump and bullet connectors for the switch. Do it right (remove the kluge wiring) and eliminate any future problems.
Jim