There is a two part "bug screen" on our ('85) Westy skylight. It attached
with velcro around the opening and a solid piece attaches to the screen on
one side permenently and the other three sides with velcro to the screen so
you can secure it to block out the sun or open it to let in air.  I don't
know if it is the original configuration or not but it IS made out of the
same material as the curtains.  The only problem with it is the Velcro
strips that are applied around the skylight are the hook side of the Velcro
so I keep catching my long hair on it when the roof is down.  I think they
would have been better off using the loop side of the Velcro on the roof
and hook side on the screen & shade.  It wouldn't be hard to make one, just
get fabric, velcro and nylon window screen material, or you might try the
Bus Depot or Bus Boys.

Wendy & John
'85 Westy,   "S-CAPE"