[mr48chev]

That switch should have Accessory and start on it along with on and off.

I'm not sure about the Classic parts "will not work with a foot stomp starter" thing because as long as off and on work that is all you need with foot stomp.
It won't work with HEI because there is no power to the ignition on a TF with a key switch in start position as it then relies on the resistor bypass wire. That happened on a lot of 12 volt key start Chevys in that if the bypass wire was disabled the car/truck wouldn't start as there was no power to the coil.

Now is the back of the switch photo your photo of your switch or just a photo you found of a 55 Chevy truck switch? You just may have that earlier switch that has Battery, ign and should have ACC even if it doesn't go to an ACC only position.