Door Conduits

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Doppleganger

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I have seen a few postings here with comments about not knowing where to mount them. My 85 has dimples for them on both the doors and the cab. Were these marks for something else?

Also - the conduits have a large end (1-3/4) and a smaller end (1-1/4). Any logic or science as to which end goes to the cab or the door? They look like fun getting the wiring started down inside the cab to begin with.

THX
 

75gmck25

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I retrofitted my '75 with the conduits, since it was before they needed any wiring to the doors (power locks and windows were not available). I think I remember the dimples you are referring to, so maybe they are just part of the door assembly. I just eyeballed it and drilled out the holes in the door about midway between the hinges. Then I lined the door frame end up so it was parallel. I put the large end of the conduit on the door, but I don't remember why I picked that choice.

It wasn't really hard to run the wiring down to that area if you stick your head up under the dash near the emergency brake pedal. You can see the white wire running to the door light switch, and you just follow the same path. It runs across a fairly sharp piece of metal to get down into the cavity, so I wrapped the wiring with a liberal amount of tape.
 

PrairieDrifter

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Here is a 79, I would imagine the big end would mount on the door, I didn't personally notice a size difference.

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Doppleganger

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I was thinking the large end on the cab to get them started, but could see it either way. I've got some vinyl sleeving like OE car harnesses have. Can get it online through motorcycle suppliers. Heat and fire resistant too. Run all the harnesses through one of those and it will fish pretty slick.

I'm pretty sure I saw a posting somewhere about those dimples being for the conduits. I sized mine up and the top/bottom dimple line up perfectly with the conduit's holes.
 

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I have a theory about the different end size thing.

Does the factory harnesses that are typically run here - have a grommet they run through? These conduits are the same size all the way through except the one end with a larger opening. If there was a grommet in the hole on the door or the cab, that larger end would go over it. I have read about leaks but cant remember if they occurred in the door or the cab.

Anyways, that might explain what end gets the larger opening and why.
 

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I installed OEM style conduits from LMC in my 85 K20. Yes, the dimples are there. To do it right, also buy the special rivets that go with them. I made 1-1/4" diameter holes in both ends and put grommets in the hole just for extra insurance. Either way you need to remove the doors to do it right. The direction of the conduit was a moot point, they work either way. Keep in mind on the cab side, once you have a hole its not a direct shot to the kick panel. There's an inner panel that you either need to drill thru or fish the wires up and over to get them accessible.
 

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To do it right, also buy the special rivets...

There's an inner panel that you either need to drill thru or fish the wires up and over to get them accessible.

Mine had screws which I thought odd but my paint/body guy put plastic push in pins in there. I need to run 2 more wires for add-ons and don't want to ruin them by prying them out so I am going to try and fish something through and make it work.

Going up and over the inner panel is how they came from the factory. It keeps everything up higher so it can't be seen near the kick panel.
 

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My doors (and everything else) is off. Wanted to drill the holes before it gets stripped.

Thanks fellas!
 

Camar068

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where do you get replacements? I'm having a hard time finding them due to not actually knowing what they are called.

thanks
 

Doppleganger

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Camar068

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I'm blind as a bat in 2 ways.

-the harness someone traded me for has them (original)
-looked over LMC and didn't notice them

lol on top of that, today I couldn't find the repaired harness. Bad things went through my mind.....oh ****...I cleaned the garage 2 weeks ago....surely I didn't put it in a contractor bag, then throw garbage on top of it later.

Thanks @Doppleganger
 

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Reading these posts from last year good info. Any hindsight updates.?
 

Doppleganger

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Reading these posts from last year good info. Any hindsight updates.?
I will have to measure the door's hole to know which side I used the larger end on. I want to say I went bigger on the cab side for an easier feed into the door, but cant remember.

I will check as now I'm bugged about it again too. lol
 

Ken B

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On my replacement doors I have the end of the door conduit still attached, it was cut away from the cab at some point so I have that end to compare to my new conduits. Any advice on how to decide where to drill hole in cab ? Use 3 dimples as reference?
 

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The dimples are where the rivets would be. That's where the boot flange goes. Super easy.
 

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