I ran into the same problem with my '82, the shocks hit the back of the bags when adjusted.
I just swapped them left for right, and vice versa.
Be sure to have a piece of wood, a 2x4 works nicely, a bit longer than the length of the shock, so you can prop up each side while the shock there is being removed. Trying to support everything, if working alone, while lining up the bushings and bolt holes can be a bit of a b*tch. [smiley=tongue.gif]
Or, as Monty suggested, remove the stock shocks altogether and replace them with a pair of Hagons. $200 and all of your problems will be solved, and the ride much improved!