Help a fella understand Federal PS pump pulleys

cudamark said

That will make it much easier to install. The plain end shafts are a pain. You need to get the same pulley you took off so the diameter and offset are the same.

Click to expand...

Is there a trick to measuring the offset? I did some research, and it seemed that the offset was measured from the back end of the pulley to the middle of the V groove. And if this is right, my janky measuring with a measuring tape came in at 1.5 inches.
...
So... where would I get a press on federal style pulley that would work? Could I just use a pulley with a shorter offset, and just press it on "just enough" that it lines up with the rest of the pulleys... or would that not work? I was looking at that march performance pulley, and thinking that maybe the quarter of an inch size difference would be a benefit. It would slow down the pump, which I was reading helps tremendously with how the steering feels.