Too much toe-out will wear both tires on the inside. Too much toe-in (pigeon-toed) will wear both tires on the outside edges.
Zero toe (pointed straight)gives you good even wear. A little bit of toe-in keeps the vehicle from wandering around over irregular road surfaces at speed (hence normal settings are for a bit of it). A little bit of toe-out gives you better turn-in (typically a racing setting).
Uneven wear from side-to-side means something is worn/mis-adjusted in the steering--one tie rod is longer than the other. In general, rack and pinion is self-centering and wear will be even between the two tires if toe is bad--unless a tie-rod end is bad. I don't know much about steering box/drag link steering, but I suspect it could be out of adjustment.
Camber doesn't have much to do with tire wear on street-driven vehicles. Negative camber will wear the insides of tires, but you have to have a lot of it and you have to have a car that will go and stop better than the average car. My track car runs almost 2 degrees of negative camber in the front (3 in the back) and I got great tire wear. (2 degrees is rather noticeable by just looking at the vehicle)--Not until I added over 150 horsepower and 12 inch rotors, Wilwood calipers, then it would go fast enough and stop fast enough to wear the front tires under braking due to excess camber.
Unless your truck accelerates and stops like a Corvette, it isn't camber, it is toe-out and you have more on the driver's side. If the tie-rod is behind the hub, it is shorter on the driver's side than the passenger's side (for left-hand drive).
A reputable alignment shop should be able to align it or tell you what parts are too worn to do the alignment.
