Hey Big,
First, you can download the CEN Nitro Handbook which has all the info you will need for your engine, including the factory settings of your needles and how to tune your engine for any climate. For your convenience I have included the link so you can download the Handbook.
http://www.cenracing.com/downloads/nitrohandbook.pdf
Second, for your situation, you will need to adjust your idle circuit fuel mixture(the one for the fuel) first. And you will most likely need to adjust it for less fuel as it seems you are at a higher elevation with thinner air. And just keep in mind the old phrase "Righty Tighty, Lefty Loosey" Tunring the screw or Needle right for less fuel, tighty, and lefty for more fuel, loosey. Be very careful not make your adjustments too much, only an 1/8th of a turn at a time. Otherwise you could miss the "sweet spot".
Good luck, I hope this has helped some, but if you need further help, feel free to give me a call using the telephone numbers provide below in my signature. I will be happy to help!