OK lots of decent advice so far.
I've been running a 34' Fleetwood Bounder for a few years mostly in or around the Rocky Mountains.
First of all you did not clarify which Banks system you have. Is this the RV headers or the Turbo? Both potentially increase the power to over 300HP. More energy means more heat and more heat means keep your cooling system clean, especially at altitude where the air is substantially thinner.
Its hard to add another electric pusher fan but cam help.
I don't have any banks kits and I can still overheat at altitude when hot outside. I added a transmission cooler and a thermostatically controlled high volume fan for the cooler. Its located so that it doesn't add heat to radiator air intake.
Headers: Make sure they are wrapped with high temp header cloth to lower the heat radiation on climbs. Otherwise expect melted wires and fuel issues.
Turbo: Usually comes with all the requirements but also runs VERY hot.
Downhill: & Avoiding a runaway.
My biggest issues beyond the rad overheating was going down long steep sections at altitude. The beast is heavy and pushed downhill like a skier.The 460 only helps a little to reduce the acceleration.
So keep the speed down, don't over rev and NEVER use your brakes continuously (Emergency excepted).
You apply solid pressure to significantly reduce the speed, typically only for a few seconds (5-10), use the engine as able to try to keep speed down, (20mph & 4 ways on), let the brakes cool as long as possible, repeat. Pull over for cooling if you feel the brakes are getting too hot.
Hope this helps.