1957 Passenger side firewall penetrations identity help needed

[valhalla 4771]

I'm reinstalling all wiring. Dash is still uninstalled. Did not make good enough notes/photos of the engine compartment firewall when I pulled out old wiring. See attached photo of a 57 I saw at a local show. Passenger side firewall above the heater box. I see the black wiring harness coming around at the top headed to the regulator and horns.
There is a fat black cable/hose going through a grommet. Is this the antenna wire? If not, what?
There are two red wires and a black cable/wire that appear to go through the firewall in a single opening (no grommet that I can see). I'm thinking the cable might be the heater control cable. But any positive identification will be greatly appreciated.

This page contains affiliate links for which I may be compensated. As an eBay Partner, and Amazon Associate I may be compensated if you make a purchase at no cost to you.

 

[zeroroadkill]

The top grommet is for the heater box cable.The one closest to the heater box plenum, are the wires going to the fan motor and the heater control valve vacuum line.

 

[Pink T-Bird]

If by heater box cable you mean the butterfly valve to let air to the blower motor then yes. For me the heater box is the pressed cardboard assembly inside the car where the air can be diverted to the defroster or sent to the outlets towards the floor.

On most cars I've taken notice of the vacuum hose to the heater valve on the intake manifold and the red and orange wire to blower motor come therough the same hole. On my car there s a grommet but I don't know if that is "correct" or prior owner's choice.

 

[Ward 57]

If by heater box cable you mean the butterfly valve to let air to the blower motor then yes. For me the heater box is the pressed cardboard assembly inside the car where the air can be diverted to the defroster or sent to the outlets towards the floor.

On most cars I've taken notice of the vacuum hose to the heater valve on the intake manifold and the red and orange wire to blower motor come therough the same hole. On my car there s a grommet but I don't know if that is "correct" or prior owner's choice.

I don't think there was ever a grommet there. Just body dope. Any electrical dept. in a big box store has strips/roles of buttle. Basically uncured rubber you can stuff anywhere.

 

[doug7740]

The right side vent cable went through grommet number 353626S, but the heater valve vacuum hose and the blower motor wires were sealed with black calk.

doug7740
1955 Thunderbird Blue