318 top and bottom pulley's for a power non air car

Let me get this right as long as I don't run juice 12V to the compressor or should I unhook one belt.

I know as long as you don't turn it on it isn't pulling much power from the motor . The car I'm putting it in is a non air car so no juice yet 12v.
At some point I might run a under the dash a/c unit off the compressor.
We'll see Thanks for the help

So I don't have to worry about capping off where the hoses go?