Dome light courtesy door pin switch install help - 74 C20

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Fightin Rooster

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Hello,

I'd like to install pin switches in the doors of my 74 C20 to activate the interior dome light. There are none installed now.

There is a plastic cap over a hole in the door frames right where you'd expect. I removed the kick panels with the side vents and have access to the back side. The problem is I cannot reach all the way to the door frame as there is sealed structure which is essentially the A pillar continuation.

I have installed pin switches in doors before and I needed to get to both side to fasten the nuts and set the depth.

LMC sells 36-0622 COURTESY LIGHT SWITCH CHEVY GMC 73-84 theoretically specifically for this however it looks like it only bolts into the front, doesn't have a depth setting, and looks kinda long from their drawing.

Then of course, running the wire will be an issue but I'll handle it.

Does anyone have experience this part, or a recommendation, or advice?

I'll also be running speakers (and maybe power windows) in the doors. Perhaps if I put a 1 inch hole for the wires very, very close to the pin switch location, I could use that to access and fasten the rear pin switch bolt.

Thanks
 

gmbellew

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The switches only screw in from the outside of the jam. Hold the pin while you screw it in so the wire doesnt get too twisted. The depth adjusts with a sliding mechanism. At least that is how it is on my 1990 suburban...
 

PrairieDrifter

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You have to order the correct switch for your cab year, I believe there's two or three different switches. Then it only threads into the sheetmetal, no access to the backside unless you cut an access hole which is unnecessary.

If really worried about it, mount a nutsert into the sheet metal and thread the switch into that.
 

Grit dog

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See if you can fish a hard wire from the hole in the door frame to the front of the kick panel and use it as a fish tape to pull the wire through.
As mentioned, you don’t need to get to the backside. Switch screws in from the front with the wire already connected.
 

75gmck25

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I have factory switches in my ‘75. If you remove the plastic kick panel you will see a metal panel behind it. If you then reach up to the top of the metal panel you will be able to snake a wire up over it and into the void behind the door switch.

My switches are corroded and don’t make a reliable connection. I bought replacement switches, but the threads are smaller and don’t fit tightly in my ‘75 door frames. I assume there are two different thread sizes for the OEM switches. The frame appears to be just a thick spot with threads cut in it, but since the hole is too big for the new switch I can’t make it work easily. I think the solution will be a nutsert/rivnut.

Bruce
 

Grit dog

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^Theres a couple things you can do if the size of the hole is “close” and you want to use those switches.
I frequently do this with stripped threads (not on structural stuff).
Use a piece of 2 of small gauge stranded copper wire. In your case probably strip off the insulation as the switch needs to ground to the body.
Thread the switch in with the copper in the hole bent 90deg so it stays put. The copper will help the threads grab. Trim up the “tag” sticking out after wards.
Or, and this sounds more cheesy but will work. Wrap the switch threads in strip of aluminum foil and thread in.
 

Gene76

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I just joined this site and found an older one on installing an courtesy light switch mine is a 76 chevy c10 I got two new ones from LMC, but they do not have a tech person anyway it is a 36-0622. The question I have, is it suppose to self adjust as I tried closing the door, but it appears to long any advice would be appreciated.
 

bucket

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I just joined this site and found an older one on installing an courtesy light switch mine is a 76 chevy c10 I got two new ones from LMC, but they do not have a tech person anyway it is a 36-0622. The question I have, is it suppose to self adjust as I tried closing the door, but it appears to long any advice would be appreciated.

They "self adjust" by simply closing the door. HOWEVER, some applications will cause damage to the switch if you aren't careful, so if they are excessively long it is best to bop them in a little bit with a soft blow hammer before closing the door.
 

PrairieDrifter

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I just joined this site and found an older one on installing an courtesy light switch mine is a 76 chevy c10 I got two new ones from LMC, but they do not have a tech person anyway it is a 36-0622. The question I have, is it suppose to self adjust as I tried closing the door, but it appears to long any advice would be appreciated.
The first ones i got were too long, so they ended up smashing themselves on most used doors.
 

bucket

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I'll bet @Keith Seymore remembers how the switches were adjusted at the factory. There's probably even a story to go along with it?
 

AuroraGirl

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You must be registered for see images attach

if you can i would find a more modern vehicle which uses a plastic plunger. less likely to rust in place and also quieter and etc. Gmt 400 maybe?
 

Gene76

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I tried bumping mine in a vice doesn't move broke now, maybe the plastic is a good idea if it fits in the hole and long enough problem the original are grounded to the body only one wire system
 

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