Debra,

We use 12V dash fans in both our Vanagons.  For one, I built a
bracket out of an erector metal set that hooks under the ashtray to
keep it in place.

The other one we bought came with a spring clip and I just remove the
ashtray and clip it into the lip at the edge of the hole.  Both
setups are removable for the winter.

It makes a big difference in airflow.

One other idea I've heard of, but haven't tried: clip a fan near the
rear hatch and wire it into the rear defroster.  The defroster
circuit has plenty of amps and you typically don't need it much in
the summer when you'd want a fan.

Hope this helps.

-Karl

Karl & Kristina Bloss - Hurricane, WV
'85 Westfalia Camper "Fred"
'87 Westy Weekender "Bev" For Sale: http://members.citynet.net/bloss/vw/
Almost Heaven West Virgina VW Club:  http://wvvw.org/
"Bound to cover just a little more ground..."