Anyway to answer your question... The under dash air vent assembly is easily removed. Nothing but hardware involved. Remaining system works just as it did.
The dash air vent assembly is easily removed with a deep well socket. Removing the assembly leaves 2 large bolts sticking out of the underside of the dash and a gaping hole in the air box assembly. Even without the compressor, when selecting A/C unheated outside air will come blasting through this hole aided by the fan. Max A/C will recirculate cabin air.
The default setting on the door in the air box assembly for A/C is closed. Find the vacuum line for the dashpot that opens the door and plug it. This will keep air from coming out through the hole left by removing the dash air vent and not compromise the rest of the control's functions.