i have a custom rear hatch speaker setup from a vanagon i parted out..  this
was a really nice custom job.  you will need the heavy duty hatch struts
though.   i think i am keeping this setup for my own van.    the 6x9 speakers are
mounted in custom plywood frames which are screwed to the INSIDE of the hatch
panel lip so they dont protrude or interefere with the stock hatch panel.
then the stock hatch panel was cut out in the appropriate areas so the sound
could come through (two large ovals were cut into the stock hatch panel) and then
the hatch panel was completely recovered with grey velour maching the seats
and rear cushion..so the sound comes right thru, unmuffled.  (use whatever color
you want)  and  the finished look is awesome, and looks completely stock...
you cannot even tell you have speakers in the hatch..  wires are run in thru
the same hole as the rear wiper wires.

easy upgrade with big sound improvement.

chris