Towing my camper at 10,000ft.what do I need to worry about?

Your gasoline usage will go to pot just as bad as the horsepower output from your engine. I have seen many a trailer puller run out near the top of a very long climb, 15-25 miles. Keeping the rpm up is necessary to avoid fouling plugs with gas rich combustion intake. I fouled a carb truck badly my first time. Electonic fuel injection helps but can still be a problem