is Alternator kaput??

[siambisg at uchastings.edu]

I mistakenly put in a new 90amp voltage regulator onto a 110 amp alternator, and the battery is not being charged.  I have 2 main questions:
1.  Did I destroy the 90amp voltage regulator by running the engine at idle and revving it a couple times?

2.  Considering the implications of question 1, is it likely the alternator is kaput and needs a rebuild beyond the voltage regulator?  (i.e., would the lesser voltage regulator prevent the otherwise proper function of alternator)

Tuesday night (after running my seat heaters on high frequently) my 88 90q barely made it home with the battery warning light on and the idiot lights on the dash on as well.  I pulled the voltage regulator off and found the brushes badly worn (4mm & 2-3mm).

I've now replaced the voltage regulator with a new bosch unit, but when i turn on the ignition the battery idiot light does not come on, and with engine running the voltage on the battery reads only 12.14 volts or so.

The car has 208,000 miles on it so it's possible that the brushes & something else in the alternator failed together.

Thanks,
George Siambis