What doesn't make sense is the "bigger water pump pulley" part. It should be smaller, way smaller than a stock water pump pulley to compensate for the bigger crank pulley diameter. I have a SolidWorks blueprint I drew up for a 162mm crank which would compliment a 65 SC pulley perfectly. I did disassemble a cracked unit to get the proper groove measurements. Maybe it's time to machine it now.....