Thanks in advance. I'm going to get rid of the air on the car. The compressor clutch froze up 2 years ago and tore up the compressor (wasn't charged yet)so I just took the Pistons and rods out and filled it with oil. It's been fine but it's time to get rid of it. I need to know what pulley to use for the water pump. After measuring I think a stock non air pulley will work but I'm not sure. It's a 400 block with dual pulley alt. The back of the pump pulley would be right at the bolts but after looking at pics it looks ok. If I have to move the alt out a bit that's fine. I don't want to buy without the advice from the guys who know. Take care