I've driven carbed cars over the Rockie mountains and back down and didn't have any problems starting them when properly set up. Your nit picking, there are not separate carb choke specs for high elevation so the manufacturers never thought that the specs given wouldn't work in either application.
BTW, the C3 carbs (1981-1986 for the most part) will compensate for elevation as the fuel mixture is adjusted 10 times a second. The system has a map and baro sensor on it, as well as a O2 sensor and is ECM controlled.....................
If your talking about fuel injection to be a deal breaker it's more cost efficient to retrofit a aftermarket system to a Stratosteak engine than do an engine swap.
I'm standing by what I said, IT'S AN EXCUSE NOT A REASON.