The Jim Carter listing listed worked exactly as described. Short shaft pump plus flat back "216 style" fan. No spacer. No belt incompatibility. Clears radiator. No muss, no fuss. 1962 engine in 1951 truck. Easy peasy.
The only remaining questions/issues I see:
* Sub-optimal fan placement for cooling. No issues for thus far for me.
* The whole car/truck balancer difference. Is that why the OP had fan clearance issues!
1. So there is the answer for full pressure truck motors into an AD without relocating pump to a higher location. From JW51. Using J. Carter's parts or equivalent. Do this and you will have no fan to rad problems and no fan to balancer problems. It may or may not be optimum for cooling your motor.
2. A full pressure motor into an AD can also be done with Pre68Dave's relocation plate and proper older style pump and balancer. If relocation is desired.
Some folks will reuse the old parts from the old motor. Some folks will have to buy them used/new. Using Dave's advice. This will also have no interference problems and will be better cooling if you need that.
I would suggest that any other way is a waste of time and money. You can see you don't need spacers or worry about groove widths with these options. It is possible that some vendors do not have a grasp of the situation or have their own ideas. I hope I have said all this correctly. I hope it finalizes this post.
J. Carter has some good info on this. Explained on the description of the pump, fan and plate. He fails to distinguish 55.1/55.2.
He does say 37-62 on the pump but I think he is saying that because it's used up to 62 with an adapter plate. Not because it is stock 62. As evidenced by the description of that short pump. When you search his 1962 water pump you get a 55-62 stock pump.
No info yet for a full pressure car motor that I see. Seems like one of the two ways above would work after swapping the necessary parts. Dave's page did not say there was interference with car motor parts, only that the "ratio" may cause over spinning. He does explain what balancers to use.
