Have the 90GL acting crazy here.  It's been having the dim,stuttering
alternator light at startup here for the last few months(4-5 seconds
worth) and seems to get worse as the temp drops outside.  I thought
it was a loose alt belt, but tightening it didn't solve the
problem.  Now that I need headlights when I go to work in the
morning, I notice right after the alt. light disappears, the
headlights get somewhat brighter, not that they were really dim
before, but there is a difference.  Is this a voltage regulator issue
or am I needing to spend bucks on the whole alternator enchilada?  Is
there a semi-simple test to diagnose one or the other?

Thanks In advance

DM&FS