5K Pull to the right

[Steve Sherman]

I recently had my 87 5KTW aligned, a 4 wheel job by one of the better
shops in town.  I did this partly because the summer tires were wearing
on the inside edge and some to improve a slight pull to the right.

They fixed to tow-in which should take care of the inside wear, but
noticed but could not correct the pull.  It is a gentle pull that on a
flat road would have you change lanes completely after 20-30sec at
65mph.  Very noticible but not horrible, just means you can't take hands
off the wheel for long.  The alignment guys said that they saw no signs
of a wreck or bent parts and toe and camber were dialed in to spec.
They did say that the caster was out in front, but that there was no way
to adjust this, but they did not think that was causing the pull.

I've tried moving tires around, and changing tires, and this alignment
but cannot loose this pull.  The pull is there under power and while
coasting.

Any thoughts on what might be causing this and how to fix it.

TIA