this evening i took an old vanagon gas tank, laid it on the driveway, and
used bricks and boards and tape to build "walls" around the saddle depression
(only on the leftmost side - the saddle where the aircooled vanagon heater duct
would go, if it was an aircooled)   i left the depression for the coolant tubes
and shift linkage to go thru.   i then laid plastic sheeting over it.

i took an empty gallon milk jug,  filled it with water, and slowly started to
pour water into the plastic sheeting lined "saddle".  i emptied 3.5 gallons
into the saddle area..   then there is the area at the front, which rises up,
that's another half gallon im sure..

so anyway we're talking about a approx. 4 gallon fuel increase with modifying
the stock 2wd vanagon gas tank, in the way i suggested...

this could mean another 75-100 miles out of a tankfull (depending on what
your gas mileage is and what engine you're running)

i'm going to have one made for myself..  if it turns out well, would there be
enough interest in this?

chris