how would i go about installing a digital gta heater/ac control switch?

 

Thats a good question... I want to know the answer to that one too....

 

the answer is pretty simple but the parts needed aren't simple to find these days.
You have to have the digital dash control unit for one,and the circuitry under the dash on the passenger side.
If you have these parts,you just simply repin the digidash head unit according to your analog wiring schematic.
Also,the digidash faceplate is diff. so an analog dash radio trim plate will not fit if you put the digi-dash hvac head unit in

 

ok thank you for clearing that up