Allan,

I recently had to remove my cover and tried the suggestions that have been
offered so far.  I even tried squirting WD40 along the track to no avail.  I
had purchased a new trim strip to go in there and I finally realized that
the round part of the trim strip at the top (the part that shows) was hard
and would not let the cover pop off.  So I carefully cut that little bead
strip off with a box cutter knife and then it would pop off without too much
work.

I had a couple of places under the strip where my knife had scraped the
paint so I cleaned those spots and repainted (even though they don't show)
before I put the cover back on.

That's my experience.  YMMV

John Graham
88 Westy, Charlotte, NC