Rocky
Thank you for your response.
The ideal height would be somewhere above the cloud line. This is probably around 2000 meters. My research says the Nebia trange in the Southwest is drier than the central mountains, although lower in elevation. Elevations in Nebia are up to 2300 meters and up to 3000 in the central range.
Higher elevations have a clearer view because the atmosphere is less dense. And above the cloud line and dry means fewer evenings with viewing blocked by clouds.
If you are aware of any observatories, I would be interested in contacting them.