Bob, Thanks for the heads up and the following is no disrespect to you. The first item is a good setup should clear headers. It looks like the same setup on a 66 C20 I worked on this morn. The 66 has what appears to be factory power steering. The pulley on the water pump has three groves, two that match the harmonic balancer on the 250 and a third for the PS. The one for the PS is set about 2" closer to the radiator and about the same diameter as the PS. The second item is I think from an integral head and probably won't clear a set of headers. There may an advantage to these setups, since some of them used an air pump also. I can think of a nice air pump I'd like to put on it named Paxton. :-) Now if I could only get to the pictures on my digital camera.
Larry
68 C20 327 daily driver
63 C20 292 Camper truck
65 C10 ? Custom Cab AC,PB,PS,$flasher