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*72lb4x4* · 09-04-2006, 10:54 PM

A couple bits of info useful to those who have trucks that aren't wired normally, or thos whose POs have gotten creative with...

The resistance wire has (or mine does) a fabric sheath around it, and its one down from the top left in the firewall plug. That's assuming that the tan wire that connects to the brake proportioning valve is in the top left. The wiring diagram for my 72 says its pink and black but the outer fabric is actually white after thirty odd years.

The location of the connector in the firewall plug is useful if you want to remove the R-wire and replace it with the #12 (with fuse) needed rather than run another wire. If you go this route, its more work, but the result is better.

BTW: wiring harness tape is available from Eastwood, etc. and is better than electrical tape. Wiring harness tape is wider and not sticky on one side. The original harnesses used this tape. At the start of the wrap, black duck tape was used to hold the tape in place.

My truck has had several mods done all in red 12AWG wire and I still have a few to get rid of, including the HEI and starter solenoid. I was looking at the harness today, but my skills with the camera are nonexistent so the pics are furry.

09-04-2006, 10:54 PM	#4
72lb4x4 Account Suspended Join Date: Jul 2006 Location: DFW Posts: 1,427	Re: HEI conversion A couple bits of info useful to those who have trucks that aren't wired normally, or thos whose POs have gotten creative with... The resistance wire has (or mine does) a fabric sheath around it, and its one down from the top left in the firewall plug. That's assuming that the tan wire that connects to the brake proportioning valve is in the top left. The wiring diagram for my 72 says its pink and black but the outer fabric is actually white after thirty odd years. The location of the connector in the firewall plug is useful if you want to remove the R-wire and replace it with the #12 (with fuse) needed rather than run another wire. If you go this route, its more work, but the result is better. BTW: wiring harness tape is available from Eastwood, etc. and is better than electrical tape. Wiring harness tape is wider and not sticky on one side. The original harnesses used this tape. At the start of the wrap, black duck tape was used to hold the tape in place. My truck has had several mods done all in red 12AWG wire and I still have a few to get rid of, including the HEI and starter solenoid. I was looking at the harness today, but my skills with the camera are nonexistent so the pics are furry. Last edited by 72lb4x4; 09-04-2006 at 10:55 PM.