64 and 65 race hemi pulleys have the large or deep double grove in the alt. The the crank and water pump have the same size groove. The only difference between the max wedge crank pulley and the race hemi is the race hemi is smaller in diameter. Only the alt pulley has a part number it. Repops are made of all three.The alt repop does not have the part number. The race hemi balancer is the same thickness as a std wedge motor but it has a finer finish on the outer ring instead of the turned look of a stock one. I have seen an NOS one unpanited and it is easy to see the difference. It had a ink stamped part number on it. I have a picture of mine but it is hard to see the difference in a picture. It looks like it was ground with a stone instead of a steel tool. Jim Krammer does sell the repops.