I believe there are two styles of manual wipers. The Judging Guidelines doesn't describe the differences in the two styles, maybe the next revision will. The first is the CCPU style that has the longer shaft that fits through tube on the windshield frame. The second type is for an open car and has a shorter shaft that goes through the top part of the tubular windshield frame. I don't know the shaft dimensions, but the difference is easily identified as there is about 3/4" difference in the shaft lengths. 1955cj5, your wiper might have been original made for an open car, as it looks similar to an open car wiper with a shorter shaft.
Rusty Nelson