'94 SC2 Brake problem and a clicking noise problem

If your steering wheel doesnt shake then sounds like the rear rotors are causing the shaking.To make sure drive the car at the speed you normally feel the vibration then make sure you press and hold the ebrake button all the way down then lightly pull up on the ebrake arm while holding the ebrake release button all the way down.Just do this for a few seconds long enough to see if you feel that******** feeling.Also do they put salt down on the roads were you live?Sounds like since you replaced both rear calipers.If there is movement in that rear hub replace it before it locks up or breaks off and you loose a wheel.

That loose hub could cause noises also if you used poorly made brake pads that have too wide of a channel the pads silde on can cause cicking while braking.From the pad walking back and fourth.

Actually the steering wheel does shake a little at the beginning of braking.

That would be the front rotors being warped i would also try what i suggested with the ebrake to make sure there isnt any warped rear rotors.Saturn also had a problem with the earlier built cars like yours the brake switch under the pedal wasnt adjusted far enough away from the brake pedal causing a little fluid pressure to be in the brake lines causing the brakes to drag and make the rotors and drums warp.We were even checking the brand new cars before we sold them to make sure the brak switch was adjusted correctly.You also never answered my question do they put salt on the roads where you live and drive?Also i would inspect the pads to make sure the pads channel isnt too wide causing the clicking while driving.