high output alternators

I recently purchased an 04 deville and will be upgrading the sound system.  Has anyone here upgraded to a high output alternator on their northstar?   I am basically trying to find out if I can find a bolt on upgrade or if it will require making a bracket.   Thanks.

i dont have an answer on the bracket question, but you may also want to consider installing an additional battery .. like a red top optima or if you use the sound system while parked, maybe  a marine (deep discharge) optima (i think blue top?).

Yes, that is the plan.  I have a yellow top optima and am upgrading the alternator to be able to handle both batteries.  I am going to the dealership this week.  I will see if they can give me some information on it.