I'm at 6200', but took the boosted big block dually back home to MI dragging my enclosed car hauler, loaded it, and dragged it back to CO. As previously stated, proper fueling and timing is key. The computer does the rest. It sees the additional airflow, it see the boost, and it adds fuel and pulls timing accordingly. It also sees the elevated IATs and pulls timing there too. People boost stuff all the time on daily drivers at lower elevation, nothing dangerous or unusual about it.