On a 72 Chevelle, I removed my A/C but kept the harness. Which wires are still needed? Blower motor, from the original 'vapor box' and to the controls?
I need heat and defrost. Thanks.

I did the A/C delete on my '70 last fall. If I recall correctly, the only wires you don't need are the compressor clutch switch and the refrigerant low pressure cut off switch. Everything else is still used. The heat and defrost functions are controlled with vacuum.