Sirrick, I haven't "Dove In" to my AC wiring yet, but is it possible the idle stop solenoid is actually a fast/high idle solenoid to bump up the idle with the added load of the A/C compressor? The solenoids are visually /functionally the same/similar but I'm just not sure if the stroke/travel is the same, it would be adjusted differently, to maintain the idle speed with the extra load instead of killing the engine on shut down. The full throttle switch is for reducing drag while trying to pass/climb a steep hill... and to protect the compressor from overspeed as well, this also has the added benefit of adding less heat to the cooling system during its' highest demand. Just some points to consider, or research before deciding on your final/next plan of attack. As for a RANCO switch,
Sorry I couldn't be of more Help, Harry.
I'm not a hoarder I'm a preservationist 78 Monza Spyder (~Soon(ish +/- I guess) To Be 2+2 with Spoilers)