I was rooting around on the Internet and found this way to make an extended gas tank for your Honda, looks pretty easy, and might work!
Sorry about the address, the guy is crass.
http://lnk.in/3wm5
Ozz
'07 3400RL 2nd RTU
2 Golf Cart batteries 3,000 watt inverter, automatic transfer switch
Honda 2000 Generator, Maytag's with 220 Dryer
Stationary domed Sat. dish, LCD 12 Volt Amp gauge, LCD Tank Monitor
3 added 120 volt outlets, On Board Air; 12 Volt Viair 450C compressor
2006 Ford PSD 4x4 Off Road Lariat, Hadley Air Horns, Truck inverter with 110 volts: laptop, Color Backup camera, Firestone air bags,Husky air ride roller hitch, Awning lock