Hi,
my two cents.
before the pump so that you can see what
may have gotten into the pump. also, in a more
serious point i have seen too many filters after the
pump that were ziptied or clamped to the alternator
in any number of fashions. additionally, i have seen
even more filters after the pump that just bounced
around above the alternator. finally i have serviced
two cars that were brought in after a filter broke open
over an alternator and had a fire.
for what the filter actually does in this type of service
having it before seems to be the safest and easiest
to replace.
good luck
stone