In order to make life easier don't try to work around the alternator, just
take it out so you can get to the hose clamp and the upper bolt which by
some strange coincidence just happens to be slightly longer than the space
between the bracket and the fan shroud.  You will need to put the car up on
jackstands to get to the lower attachment point which is conveniently
reversed (facing away) and inaccessible if you are using a standard
ratchet.(I wound up using an offset boxed end wrench.)  Once both bolts are
removed the unit will just drop out, so make sure you don't leave any
important parts of your anatomy under the car.  Once removed you will
discover that you need to transfer the pulley from the original to the
replacement unit.  Loads of fun trying to break lose those three bolts that
haven't been turned since the car was assembled.  (I used two ratchets, one
set to tighten the other to loosen, you can get two of the three bolts off
pretty easy this way, have fun with the third one, unless you remember to
break lose all three before you begin removal.)
Upon reinstalling the pump you have to put the top bolt in first, (trust me
on this) but the pump will only go in from the bottom, so you have to
balance the pump on the subframe within arms reach from the top, (did I
mention your car is on jackstands?) reach down between the brackets and the
fan shroud and try to lift the pump into alignment with the holes in the
bracket, (Which you can't see from the angle you are working.) and with one
hand holding the pump in perfect alignment try to get that oversized bolt to
start in to the hole cast into the pump body (Right about now you discover
that the replacement pump is 1mm longer than the original.)  Your fingers
will eventually tire, you will let them relax the pump will crash to the
ground and you get to repeat the process.  Eventually I figured out that the
bushing pressed into the bracket can be pressed back out (using a decent
size channel lock pliers) so you can make room for the new pump.
If you try to avoid all the trouble of lifting the pump in to place from the
top by anchoring the pump using the bottom strap first since you are already
down there anyway, you will discover that the strap will quickly loosen and
rotate about the single bolt screwed into the block causing alignment
problems.

They just don't build high quality stuff any more.

I lucked out on mine. I loosened the surpentine, put a wrench on the
pulley to get it moving a bit and viola.  Course mine only has 43,600
miles on it, but it is an 85 LX.

"But now is the time for the younger men to lock in rough encounters,
time for me to yield to the pains of old age. But there was a day I shone among the champions."

Homer, The Illiad, 23.715-719 (800 BC).  King Nestor of Pylos.