My 91 has started making a squeaking and clicking noise down by the alternator. I'm not sure what is doing it, it only does it on some days. It's not really a squealing, because it sounds like it squeaks only once per rotation. Do I need to tighten my belts? Also, when I come to a complete stop my headlights get pretty dim along with all of the lights on my dash. Could these problems be related?

 

sounds like a bad alt bearing on the pulley, a loose belt or a starting to go alt.... i would say yes, the 2 problems are related...try tightening the belt first.

 

yup its a loose belt it happened to me
it will cost you about 10 15 bucks or less

 

Could also be like mazdaspeedwest stated, Your Voltage Regulator/Altenator going out.. I have the same problem but have not fixed it yet.. I have a 94 DX.. I had the same problem on my old 84 toyota pickup and it was the Voltage Regulator.. So that it where I will start on my Pro.