Well, based on what you said, it only squeals when accelerating, which would be putting a load on the alternator. My '90 Cutlass did this and so did my '93 GMC V6 truck. Kind of hard to reproduce the noise when not under those circumstances. But, take off the serp. belt and turn the alternator pulley by hand. See if you can feel some week grinding or something akin to sounding like sandpaper rubbing against each other.