Karl
the wrist pins are very hard and they dont often scratch or distort
although they do tend to accumulate varnish between the piston and the
bushing.
the wrist pin bushing in the rods is a brass bushing and and even when
it looks good the leading
edge of the bushing often has a burr I would think this to be the case
because  you said this pin fits the other con rod bushings
you need to try the pin from both sides and see if the pin is free on
one side and not the other
if that's the case the trim the tight edge of the bushing with a sharp
blade I use a three angle blade I got from sears. If the scratch in the
bushing is the problem lightly sand the bushing until the pin is free.
never test install the pin unless the bushing and pin is clean.
installing the pin with a tight bushing will result in a very early
failure as the bushing will become loose in the rod. I check the wrist
pins after the piston and cylinder is installed with a little wiggle
this lets me know if the pin is still free. only then do you push the
cylinder down in place
I hope this helps
Bob Donalds
http://www.bostonengine.com
as always
all rights reserved

Karl wrote
I'm attempting to reinstall the pistons, and am having a problem with
one of
 the wrist pins not fitting in the connecting rod.  It fits into other
rods,
 but not the one it came off of.  It will go in with some effort, but
won't
 turn; at least not my hand.  I did manage to put a faint scratch in
this rod
 while removing the piston, but I don't think that's a factor