Elastoplast: sort of a self-stick double-knit moleskin. Your hands take a beating and this can reinforce any areas that are starting to get raw or develop a blister.
Sunscreen: Unless you NEVER EVER burn.
Hat: See above.
Shoes or boots with ankle support.
Spare parts: for a 1911-a slide stop and an extractor (adjusted). For a revolver- take a spare. For others, ask them at the gunsmithy, they see more handguns fail than most.
More ammo: FMJ will make clean-up a lot easier than cast.
More PROVEN magazines: cheap magazines will be a pain.
Elbow and knee pads.
Lunch every day: don’t expect to get to anywhere for lunch. And even if you could, your paying big bucks to be there, not go to McD.
Canteens, Camelback, Jug : WATER
Pencil, pen, notebook.
Sunglasses and a strap.
Spare corrective lenses.
Spare ear plugs, and/or spare batteries for electronic muffs.
Being from Colorado you are probably used to the altitude (about a mile). If you're not, come a day or two early to acclimate.
In November the weather is pretty variable, as CAR15M4 said, you probably won’t need a raincoat or a parka, but I’d bring them anyway and leave them in your room.
Have fun. [:D]