Good info ADV Grifter - thanks!
I actually have a gps track for the route through Choix to El Fuerte, but its a track I downloaded off the net somewhere and had no way of knowing if it was any good or how rough the route might be. I may try going that way next time I'm headed to Baja - would probably be much more interesting than slabbing across AZ on I-8 to Mexicali.
Ferry across to La Paz and ride north through Baja.