When Greg and I did an enduro at Infineon, we did the same thing and got a 5 minute penalty because we overfilled the tank after 1 3/4 hours by trying to put in 10 gals.
Last year, I only put in 5 gals for a 3 hour race and had most of it left in the car when I drained it after the race was over. So, Joe, the late cars will only need 5 gals. MAX and the early cars will need 8 or 10 gals.
Jim R., that fuel jug looks like a great item but it is $60 plus shipping and I don't want to spend that much for once a year use. Do you have an early or late car. If you have an early car, you would need 2 of them.
One suggestion is to do something like Charlie suggests and test it. If it works, several teams can share one or two jugs by staggering when they pit. I have a radio so it is not a problem for me to adjust my pit stop around others. We should get set up to share fuelers and fire guys anyway so we don't all have to have our own.
Big Dog