I have the three pullys, the crank pully, the water pump pully and the power steering pully. I believe them to be original to my car, 1972 SS454 4 speed convertible.

Here's my concern, my car does NOT have air conditioning, yet all three pullys (even though they have the correct part numbers) have an extra groove, which on my car is unused.

crank pully has 3 grooves
water pump has 2 grooves
power steering has 2 grooves

Is this correct, were there only one set of pullys in 72 for use with both non a/c and a/c equipped cars???

My restorer felt this was unusual, all cars he has done in the past that didn't have A/C, did not have the second set of unused pully grooves, but then again this is his first '72.

Thanks in advance for your help