Adjusting camber and caster???

My sons 73 duster was eating tires up on the out side! Could tell the camber was off by just looking from the front of the car. I adjusted the the upper control arm eccentric bolts by using a plumb bob hanging from the fender. Got the wheels set with the top of the wheel slightly in more than the bottom. My question is, should the eccentric bolts be in some what the same place from one side of the car to the other? Mine are completely different. Also I've read that you should start from zero on these settings but the eccentric bolts can go all the way around 360 degrees. Where is zero? Lobe straight up or down? Dont have a clue!! It would be nice to have some how to manual with pics on this. I'm just using simple tools (shade tree mech) so keep it simple for me.

Thanks for reading: Benson