Colorado sounds like a really good choice as far as making it a vacation as well as a meet. Seems like everyone is just under 2k miles. Most are within 1600 miles. Of Course people are more than welcome to fly in and ride in other's first gen birds.
I'd probably bring the Bird and Jeep, go wheeling part of the time and Cruise the bird the other time.
1968 Pontiac Firebird (In the works: 440ci Pontiac + Doug Nash 5 speed + posi rear = 1320 and Corner Carver Wanna Be)