neutral safety switch

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vern6.0

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Columbus
First Name
Vernon
Truck Year
1974
Truck Model
c10
Engine Size
5.3l lm7
Hey guys I'm new here! I'm trying to see what should I do. I have a 74 C10 stepside. Before I bought it it already had a floor shifter in it. So I recently redone the whole truck with a ls swap n installed a new console shifter in the floor. Now the wiring I traced I ended up finding the reverse light switch and ran it to the shifter but I can't seem to find the lead for the neutral safety switch. I don't know what colors to look for. I'm guessing whoever had the truck snipped out. So what would be the best thing? To rewire under the dash or dig deep n trace where it's been cut and run extra wire to the connectors on the b&m shifter? Again my reverse light wires are green I traced it from the fuse box. Can anyone help me? Thanks
 

kdo58

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Puyallup wa.
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David
Truck Year
1975
Truck Model
k5
Engine Size
350
i by passed mine just another thing to go wrong.
 

CSFJ

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I had a '79 in high school that had the nss bypassed. If I remember correctly, the wires were pink, and purple? Possibly one was white, (it was 20 some years ago ). The factory position for the switch would be up on the steering column, under the dash, not too far from the brake pedal.
 

chengny

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NH
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Jerry
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1986
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K3500
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350/5.7
In 1974 both sides of the NSS (the feed to the NSS - from the ignition switch and the switched hot lead that connects to the "S" terminal on the solenoid) were purple.

The easiest way to incorporate an NSS - into the currently installed circuit - would be to trace the purple wire back into the cab (starting at the solenoid).

The truck as original had either an NSS or a CSS. I don't know what you mean by a "floor shifter". Do you mean it had a manual transmission or an automatic with the select lever located on the floor?

I guess it doesn't really matter. Somehow, when you turn the ignition switch to start, power is applied to the solenoid via the normal purple wire.

Locate where that purple wire penetrates the firewall. Unless someone made an unnecessary modification and re-routed it, the purple lead will enter the cab at the normal firewall transit block by the wiper motor. I would skip the tracing on the engine side and at first just look for it on the cab side. There is only one purple wire in that group - it should be on the top row of the block on the inboard side. See the maps below.

When you find it, cut it and splice on two extension leads. Make the extensions long enough to reach your NSS (I am assuming that your new shifter has an NSS switch built in). Connect the two extensions to the NSS and you're done.

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GTME94

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Metro Detroit/Holland, MI
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Terry
Truck Year
86
Truck Model
C2500 C6P Camper Special
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454/TH400/14bff 3.73
Too me it would be worth the effort to install a NSS. You may always remember to be careful starting the truck but it only takes one time of someone else starting it in gear or you forgetting once and all of a sudden you have major front or rear end damage.
 

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