The "A" arm is the bottom part of the suspension. It sort of looks like an "A", thus the name. The inside end has two arms that attach to the cradle that have rubber bushings. That'* what Mike was referring to.
Does it do it all the time, each time you turn left, and whether moving or not? What type of bumps cause the problem? When the person who looked at the brakes said "it was just rubbing" - what was just rubbing? If it'* an issue caused by his work, he should fix it.
As far as the Olds 88, many of our members weren't even born in 1982. With a car that old, have it looked over thoroughly.
Black 2000 SSEi, Silverstar Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, drilled 180 degree thermostat, Intense FWI, PCM, shift kit, and 3.4 Pulley. Solid front mount.