Hi Bob,
Thanks for the compliment. The gas tank I'm using is a Dubro S-40 (40 oz.) tank. I'm thinking it will give me about 50 - 80 min. flying/towing time. Fuel usage is between 1 to 1.5 oz/min at full throttle per the manual.
I have a 26cc gas engined UltraStick and it flys for more than 30 min on a 12 oz tank. Most of the time I fly at 1/2 throttle any way, plus with the big planes its imporant to excersize throttle management. In the Revolution manual, they recommend a 20 oz tank. The nice thing about gas engines is the carburetor has a pump mechanism built into it so you can place the tank at the center of gravity. On my 26cc gas engine I just turn the choke on and flip the prop about 7-10 times to draw the fuel up the the engine, then turn on the ignition. Then engine will pop once, then turn the choke off and flip again and it breaths to life. (really simlar to starting my gas powered weed wacker ).
Back on posts # 52 and 54 you can see the firewall reinforcment I did and then I just gave it a coat of WestSystems Epoxy to fuelproof it all. The inside reinforceing ring is made out of two 1/8" 5-ply plywood pieces laminated togather. I also added acouple of 1/8" Ply reinforcing pieces on the inside of the sheeting ( inbetween the rails ). I would have done as Martin suggested ( incorporated in new kit ) and used 1/8" ply to sheet the forward ares but I all ready had it sheeted. I also added some fiberglass reinforcment to the firewall / rails area.

Glad to hear you got the engine mounted, that's a big hurdle to get past.

Scott