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

I "hacked" the A/C from under the hood of my '70 Duster 318 only because the system was totally empty and I don't really need it where I live. I also thought it would be nice shaving 60 lbs. from the very top-front of the engine. I had to play around with different pulleys for a while until I finally figured out that there are different depths of the crank pulley... You need a 2-groove for the crank pulley that's a little over 3" deep and a deeper non-A/C single-groove water pump pulley. HOWEVER if your system is still charged and functional and you don't want to completely convert to non-A/C then just do what the other members suggested and disconnect the power supply for the clutch magnet.