Yes, it's a 2-speed. It is one of the later-model units that shifts with an electric motor rather than vacuum. They're not as smooth as the vacuum-shift types, but they're a little more reliable. You'll need a 2-position switch on the shift handle that swaps the hot and ground to the motor, and some wiring back to the rear end. I think I've got a wiring diagram in one of my truck manuals at the farm. Drop me an email when I get back there this weekend, and I'll scan you a copy.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!