1987 Honda CRX Fan control and Alternator belt squeel

I have a 1987 Honda CRX HF that I purchased new.
A few years ago it began to have an electrical problem. I noticed the alternator belt squeeling quite often and eventually the alternator light came on. On taking the alternator appart the brushes were completely worn out.

During this time I noticed the radiator fan would come on as soon as I turned the ignition switch on during the cold months and not in the warmer months. Although sometimes the fan would start to run and then shut off.

I've talked to service people who worked on these cars and they told me the radiators would 1) build up corrosion and sometimes isolate the temp sensor in the bottom of the radiator. Thus the signal to the
fan control wasn't accurate. 2) the fan control unit under the dash would go bad and cause this condition. Thus allowing the fan to run pulling lots of amperage on the alternator and burning the brushes and commutators on the alternator rotor. 3) the main relay could be a problem.

I notice the idle surges and the fuel milage isn't but about 40 mpg where it is supposed to reach 52 city and 57 highway.

Anyone else ever experience this problem with their
CRX HF? I understand the fan control unit under
the dash is different for the HF model.