Passing Wire through the Firewall Connector

[projectRanger93]

I'm currently installing the OEM fog light switch in my '93. I checked all underneath and inside the dash and i couldn't find the stock connector, so I'm running my own wires but keeping it as stock as possible. The Yellow 12V wire the switch needs is present in the engine bay (connected to C105M), but doesn't come through the firewall connector (C105F) - the wire hole for #24 (see pics below).
How do I 1.) take off the connector and 2.) attach a wire through hole #24 in C105F? Or is it too much a pain in the ass to instead run a new wire through another firewall hole?

 

[RonD]

The yellow wire is used to activate the Fog Light Relay, in the engine bay, so its a smaller gauge low amp wire, and its the only wire needed to go thru the firewall

Disconnecting the large connector and repinning a wire, IMO, would be more work with more potential problems that its worth
After reconnection there could be poor connections or frayed wires because of their age, 26 year old wires

I would run the low amp wire to the relay through another hole

 

[projectRanger93]

The yellow wire is used to activate the Fog Light Relay, in the engine bay, so its a smaller gauge low amp wire, and its the only wire needed to go thru the firewall

Disconnecting the large connector and repinning a wire, IMO, would be more work with more potential problems that its worth
After reconnection there could be poor connections or frayed wires because of their age, 26 year old wires

I would run the low amp wire to the relay through another hole

That's fair, I didn't consider that. Seems kinda obvious now haha. To minimize potential problems, i'll run the wire through another hole. Thanks for the common sense.

 

[Curious Hound]

On my ‘93, there is a nice-sized unused grommet just above where the accelerator cable goes through the firewall. That’s my favorite place to pass wires through.

 

[Dirtman]

I use the hole where the clutch master cylinder would have been.

 

[projectRanger93]

On my ‘93, there is a nice-sized unused grommet just above where the accelerator cable goes through the firewall. That’s my favorite place to pass wires through.

Yup I've seen it and it's been used, so I'm going to use that.
Good thing the OEM switch i bought came with the connector and wires attached, or else I'd have more of a headache.

 

[Curious Hound]

I use the hole where the clutch master cylinder would have been.

Some idiot put my clutch master cylinder there. But that is a nice grommet in my F150.

 

[Dirtman]

My truck seems to run fine without it... I would just remove it.

 

[projectRanger93]

Well I connected the wires, including passing the yellow wire through a firewall wall, and they all worked with the OEM switch.

 

[Curious Hound]

Victory! Good job.

 

[adsm08]

My truck seems to run fine without it... I would just remove it.

I did that once and tried using the automatic shift function on my M5OD. The truck just tried to lurch around when cranking, but would never start.

I took it to a trans shop and said it acts weird in D, they looked at it and said I was an idiot. Still not sure why.