Just been doing this. Had to replace my inner belt (A/C, alternator belt). That's the easy part. Thing is you have to remove the outer belt to install the inner belt.
Inner belt - No, you dont have to drop the a/c compressor and no I cant seem to move or pivot the alternator (95 GXE) The tensioner pulley screw is also the lock screw for the belt tesioner. Just remove the pulley and you'll see everything. adjust the tensioner bolt full (loose, ccw) to prepare for installation. I found it more easier to move the from the bottom of the car.
Outer belt - should be the same effort, but, anything you need to do right beside the firewall is hell! Tension bolt should be easy to see. Loosen the lock screw (perpendicular to the bolt), do not remove. Then fully loosen the tension bolt (CCW). the belt will not loosen (at not on mine) when the bolt is completely loose, the power steering pump needs to be pulled or move towards the engine. I had to use a pipe to move it. Then the belt will come loose enough to remove.
intall the belts (install back the idler pulley for the inner belt), tightened the tension bolts and don'r forget to tighten the lock screw as well (for the inner belt that's the idler pulley screw).
Belt deflection shoulbe 1/2 to 1 inch with firm push of the finger
Oh yeah, I had to move the coolant reservoir out of the way (just pull that out) and the plastic mounting (unscrew). To have more space to work with.
If you have no patience you'll not finish this job. Im short and stubby which means my physical attributes is not in agreement with small hard to reach spaces. My arm wrist and hand were bruised and black and blue in some areas. Just a heads up.
Hope this helps