Again good solid connections and low resistance in your grounds are important.
I had replaced the stock alt with a third gen Ford alt. Internal fan , internal regulator. After 2 seasons the gen light would blink and the epanded scale volt meter would vary about 1 volt. Thought the regulator was failing. Nope regulator was a little loose on the rear of the alt case.
At the grounds I mentioned earlier on the transaxle and front compartment I went to the hardware and bought "external tooth" lock washers . They dig into the ring terminal and stud.
A last resort after checking all the connections would be try a different regulator. 1997 would be in the solid state era. They are cheap at the parts store , but if you still have a bad connection somewhere it would be a waste of money.
Again the search function on this forum should bring up a wealth of information on what other members encountered.
Remember to work safe , lots of juice in the battery and working on the regulator , through the wheel well you can get squashed.
The schematic JFB sent you came from The Pantera Place.
Then click on technical and there are simplified system schematics.
Good luck with repairs.