JP,

It could be that the rebuilder used a different bearing from the
original, one with a longer front extension on the shaft.

Just get a cutoff wheel on your die grinder, and cut it off at the
right length. The shaft is hardened steel, and a hacksaw won't, uh,
hack it.

Gord Richmond

I had been carrying an extra new pump in the tool box that I travel
with (along with a distributor ready to R&R complete with cap and a
fuel pump) and when a car just came in that needed a pump right away, I
grabbed it.  Can't remember where it came from but it had a bigger
bearing (and casting where the bearing is obviously) than all the other
old ones I had laying around and also a thicker flange.  Generally
looked much beefier all over and was brand new.  It went right on the
GT Hawk I was working on and works fine.  I was told recently that the
truck pumps were more heavy duty (CRS prevents me from remembering who
said that) and are a direct replacement; especially a good choice for
AC cars where the AC belt goes around the pump.  And John, once again
please look at the hub as the one I mentioned earlier was from a car
with a fan clutch.  Some buffoon had used flat washers in between the
fan clutch and the pulley in an effort to make it fit.  Could it be
that whomever pressed the flange on too far or backwards?  One side of
the flange is tapered and shorter.
Studebaker (still pump confused)George