'71 fan clutch for LS-5

[alaskacorvette]

Does anyone know how to identify the correct fan clutch for a '71 LS-5 car W/O A/C? I am looking for a good, detailed description. Thanks in advance.

Jim

[JohnZ]

It can either be an Eaton (coil-type) or a Schwitzer (plate-type) clutch; has a hole in the base for a 3/4" water pump shaft pilot (not 5/8"), and it has a 3-1/4" bolt circle (not 3") where it bolts to the water pump. At the fan end, it also has a 3-1/4" stud circle for the fan attachment, and the fan has a 2-5/8" center hole.