Hy jomichael, you'll no doubt get many answers to this question, I'll tell you the method I was taught, and use. You can do the job as you suggest with the truck jacked up all the way around, or you can do one wheel at a time. Adjust the brakes up all the way until the drum can no longer be turned, this centers the linings in the drum, now back the adjusting wheel off no more than seven notches. As to when to adjust the brakes, the feel and position of your brake pedal is your best indicator, you should adjust your brakes when the brake pedal gets so close to the floor that you cannot slide your free foot between the pedal and the floor, of course you can adjust them much sooner than that if you wish. At one time you could buy convertion kits to convert manual adjusters to automatic adjusters, I don't know if those kits are still available or not, hope that helps.
