On Wed, 14 Sep 2005 21:41:27 -0500, "Martin H. Eastburn"
wrote:

I'd use external strain gages or a load cell on the bottom support for gas measurement.
Martin [ but they cost more and won't be considered ]
Martin Eastburn
Differential pressure guage, from top vent to fuel outlet reads fuel
column hight quite accurately. The sensors are pricy from "prime"
suppliers, but I've picked up sufficient quantity for my use, brand
new surplus, for a VERY reasonable price.