Dana Overall has finished with Mark Jones' wingtank. The details are at http://www.krnet.org/wingtank/ . If I ever have to build another one, it'll be done this way. Total weight is something like 5 pounds, and you can check it for leaks before it's installed. It's riveted and sealed, so there's no welding involved. I think Dana said it holds 11.5 gallons with airspace at the top. Maybe Mark can tell us more about it...
Mark Langford, Huntsville, AL N56ML "at" hiwaay.net see KR2S project at http://home.hiwaay.net/~langford