Converting Diesel Wiring to Gas

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Shields

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Kelowna
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Dayton
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1976
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C10
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6.3
Hello Everyone,

The cab on my truck is from an 83’ diesel that was originally ordered for the Canadian Army. The cab now sits on a lowered shortbox chassis with a 383 and a super t-10. The original wiring harness has a few extra runs of wiring that I do not recognize which I believe are to support accessories for a diesel, it was also lightly butchered by the previous owner who I imagine spliced in a bunch of accessories like light bars, CB radio and a sound system. Should I salvage and convert this wiring harness to be similar to a gas wiring harness or should I get a painless harness kit? Any input would be appreciated.
 

Ricko1966

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kansas
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Rick
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c20
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350
The wiring on these trucks is so simple,I'd run,and repair what I have. I don't have a diaghramnin front of me. But I am thinking gas or diesel the only difference to the wiring is going to be you don't need the glow plug circuit,and need to relocate injector pump solenoid power to HEI power.
 

Matt69olds

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It’s been years since I converted mine. If I remember correctly, the wiring for the diesel engine ran thru a firewall connector very close to the drivers side valve cover. The heavy gauge pink wire in went to the fuel cutoff solenoid, I used that to power the HEI. I unplugged the firewall connector and threw away everything. I cut the wires on the dashboard side threw it away. I’m think the only thing that harness controls is the glow plugs.

The gauges and charging system wiring was basically the same as a gas powered truck of the same year.
 

Shields

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Joined
Apr 9, 2016
Posts
32
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Kelowna
First Name
Dayton
Truck Year
1976
Truck Model
C10
Engine Size
6.3
Thank you both...it seems that the previous owner had already removed a fair amount of the diesel wiring and I've spent the last week pulling the rest out. Wow...I can't believe how much cleaner it is under the dash with all that extra copper pulled out. I'll probably put what I pulled out up for sale on FB marketplace. Thanks everyone!
 

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