Auto/Man steering column wiring differences

[eric8]

I am looking to do a TH350 to manual swap in my 1972 C10. In doing so, I will be putting in a floor shift steering column, which obviously does not have the connector for the neutral safety switch and backup light switch like my auto column does.

Now I'm looking at under dash wiring harnesses on American Autowire's website, and notice that there aren't separate harnesses for the auto trucks and manual trucks. Only different part numbers for the trucks with factory gauges and for those without.

Now my question is, how were floor shift trucks wired from the factory? Did they all have the same under dash wiring harness complete with the same connector for the neutral safety switch and backup light switch installed under the dash? (I.e. There, but just not hooked up?) The manual trucks had no type of neutral safety switch, correct? I'm trying to get the wiring sorted out and suck at reading the factory diagrams. I want to make the wiring as clean as possible for the swap. Any ideas?

[eric8]

Anyone?

[eric8]

Surely someone who has a floor shifted manual could go look. How is your backup light switch wired? I'm sure it comes off the transmission via the engine harness (transmission type specific) and then into the firewall plug attaching to the under dash harness. (NOT transmission type specific). Are there unused connectors in the dash harness just above your steering column (where the neutral safety and backup light switch would be on an auto column shift truck?). If so, do these have some type of "jumper" installed? I really would like to figure this out for my own peace of mind!

[eric8]

.....after a lot of online research and speaking with American Autowire, I found my answer. Well, as I already knew, the manual trans floor shift trucks in 72 had no neutral safety switch. So from the factory, there was a dummy plug the factory installed into the factory n.s.s connector above the steering column to bypass (jumper) the n.s.s circuit. These are apparently no longer available although it would be super easy to make one.

Now as far as the backup light switch, the diagram shows the 18 gage dark green wire is doubled up on the back of the fuse box allowing two paths for current flow. So in short, all the factory did different with the flor shifted models is install a different engine wiring harness that puts the reverse switch on the tranny instead of the column. Buy the m/t specific harness, plug it in, and you are good to go. http://1.bp.blogspot.com/-dmJl1v1q_t...t-Lighting.jpg

[eric8]

The only GM style part I could find is this, but it's marketed for 61-65 Pontiacs. Not sure if every n.s.s is identical across the board with GM, so it may or may not work. http://fabcraftmetalworks.com/cgi/co...n&key=IN4-0700