Really depends on when you plan on coming out. We have 1 track w/ 4 different configurations. Each requiring a different ratio by at least a couple of teeth or more.
We run Sr.Max. Last 2 months we ran the Nuovo configuration and ran a 12/82-83.
This month and probably for the next couple of months it will be the Grande' - Counter Clockwise configuration. We ran a 12/79-80 gear. If you're coming from Vegas, try to make it a weekend gig. We have open practice all day Saturday before each Sunday race. You can get in plenty of track time for getting the karts dialed in. In addition the clubs offers pre-registration, Pre-tech, and overnite camping on Saturdays as well. Bring your BBQ and plan on having a great time.
This way you avoid the Sunday am crowds. Nothing like waking up AT the track, teched & registered. Only thing to worry about is when the coffee's ready.