Hi Jim -

73-79 loaf's actaully had two different alternators.  Bosch AL 75X (55amp)
and AL108X (70amp).  The 108X was mainly installed on 75-79 loaf's as an
option and the fiche says to use a different pulley assembly with this one
although it does not say what that difference is (could be that 10mm
difference).  Both alternators look identical otherwise and it could be easy
for a local independent rebuilder to get 'em mixed up.  Of course I'm not at
the office right now at 11:15 on a Sunday night, but I'll check in the
morning on the shelf to see if there is a difference in the shaft length.
 I've yer phone # handy, so I'll give ya call.

Jim / BusBoys@aol.com