I don't want use it, looking for the dash control, so I can use the signal wire in the engine bay for something else
I don't have one on my 1993 U300. I think I remember someone saying that our engines didn't have them. Might try the search function.
There are extra wires running back to the engine that end near the switch panel, and there is an empty switch, so maybe you can use one of those wires and that switch for your project.
On our '93 U280, the
ETHER rocker switch is on the left-side panel, straight down from the headlight switch, and to the left of the parking brake knob. It is a "momentary" switch. If you want to control something that requires a constant signal, you'll have to swap it out for a ON-OFF type.
There's no switch showing there
No ether on my '91 6V92.
Since our '93 has a Cummins, perhaps the ether was only offered on certain engines...and not on the 6V92?
Found a photo of my switch: