That would affect everything. It doesn't really seem likely that all the lights burnt out but I've seen it before. Did they seem dim before?
Who said it was the alt?
I think its more likely that the dimmer switch quit. Try turning it several times.
On my 96 I know it kept blowing fuses. But it could also be the light knob. Could of stripped so it doesn't catch when you turn it. But I've only ever heard of that once. I doubt the alt would just effect the cluster though