Antenna coax routing question

[Dorsai]

One of the "while I'm in there I might as well..." projects spawned by my cowl/drain cleanup effort is radio antenna repair or replacement.  Some of you might recall that when I got the cowl off I found this:



Obviously that's no way to treat coax, and that's when the project switched from 'repair' to 'replace'.

The next thing that surprised me was the routing for the coax.  From the antenna it dipped down behind the fender, down into the space between the back of the fender and the door hinges, and into the cabin behind the kick panel:



From there it goes up, behind the dashboard, and over to the radio...with yet another example of coax abuse by Oklahoma Man (a distant cousin of ):



After admiring the handiwork for a bit, it occurred to me that the routing was unnecessarily long, and that the much shorter coax that came with my new antenna wouldn't be able to follow it.  That's when the bright idea hit...what if I drilled a hole from the cowl space into the cabin, and ran the coax that way?  So I bent down to look under the lip of the cowl space to see if I could get a drill bit in there, and saw this:



Huh.  That looks suspiciously like a rubber plug coming through the firewall.  Wonder what's on the other side?



So...was my bright idea in fact the discovery of an antenna wire hole that is exactly where everyone (except Oklahoma Man) would expect to find it?  If not, what's the purpose of this hole?

And...what's the purpose of the hole that Oklahoma Man actually used to run the wire?  It looks as thought it was put there at the factory...maybe for a CB or other antenna?

The adventure continues.

[Sac79]

The plug you found is indeed for the antenna. Oklahoma Man's plug is not on my truck...

[Sac79]

Correction, I have a plug like Oklahoma Man's, one on each side in fact, I believe they are for the door speakers, which I don't have, also no holes in my doors(as in for the wires)...

[Dorsai]

It didn’t occur to me to check the other side, but in fact I have two plugs as well.  I agree that speaker wire runs are the most likely explanation.

[salans7]

Those plugs are also in my truck, which has door speakers, so they are not for door speakers. They were also on my 86, which didn't have door speakers, however the holes for door speakers were present, they were just covered with a large plug. The holes for the door speakers are a little north east of that small plug.

FWIW, my 1980 did not have the door speakers, and I had to drill the holes in the cab and maybe the doors. I believe there was a dimple in both for the drill so that your pilot hole was in the right spot. At some point I guess Ford decided to just drill all the cabs and doors and plug the holes.

As for what the small plug is for, no idea. All three of my trucks have had them on both sides, and they all had the small plugs.

[Dorsai]

Curiouser and curiouser!

Maybe wiring for power locks and power windows?  As the owner of a lowly Custom, I have no idea what power anything actually looks like.  Some days I'm surprised I don't have acetylene headlights.

[salans7]

I always assumed those went through the same grommets as the speaker wiring.

How many licks does it take to get to the tootsie roll center of a tootsie roll pop? The world may never know.  Same goes for these plugs I reckon.

[kramttocs]

Yep, they do. My truck has all the options and those holes are just plugged.
It's turtles all the way down.