Alt bearings - '88 90 Q

[tihol tiholov]

Hi all, 
I suspect my alternator bearings (air cond - prolly 90 Amp) are
producing the squeeking, that makes the car  sound a bit like a K-car or
a hay cutter.  I don't hear the noise inside the car, just when standing
at the front.  Does any one have any info on those bearings and the ease
of replacing them?  I'd rather not swap the whole alt - it works fine
and plenty of brush material left.

Also a question with a possibly dreadful answer: does the water pump
bearing sound similar?  The pump is over 140k km old, but no leaks ... 
I will identify the source of noise but it's not pleasant outside.

TT