The Pecos river originates in New Mexico, then flows south to join the Rio Grande in Texas.
Canasta Flats is named for the popular card game, Canasta.
Bugs, in caricature, appears in the opening credits card, engaging in several cowboy like activities.
Bugs mentions he'll carrom a shot. This is a reference to a popular board game that originated in India. The object was to ricochet playing pieces off the board's corners, much as Bugs does with his bullet.
The background artwork had become more abstract and modern as design tastes changed from the mid century to the space age sixties.