Carbs, Mountains, fuel/air mixture... lets talk

[Longhorn Man]

Vehicle;
Bone stock 72 burb, 402/TH400/quadrajet carb. only mod, brand spankin new HEI. Fresh tune up, plugs wires, whole dist with cap/rotor/coil.
Will be towing about 3000 pounds of spare parts, gutted parts truck, and mountain dew.
I'm having concerns of the air to fuel ratio getting too rich when I go through the mountains. I'll be leaving from Seattle, which is pretty much sea level... give or take a few feet, going through the mountains and the high plains, and ending up here in Ohio, which Columbus area is 900-ish above sea level.

Questions;
1. Would I make it through the mountains without messing with the carb? I know it won't be optimized, but would it do it without fowling out the plugs every 10 miles?
2. Been recomended (by non car guys) to travel at night, cool air = dense air... makes sence, would it be enough though?
3. Same guys as above, said ditch the stock restrictive air cleaner... even go without for a leg of the trip, let it take in all the air it can
4. Lower octain fuel would be better in a rich condition right... les resistant to ignition, try and get a quicker burn out of it?

Is there anything I am forgetting?

I have NEVER messed with a quadrajet, I could probably screw one up in short order, so i'd rather leave the sucker alone if it'll make it through the thin air and just get worse MPG.