A 124 amp alternator from a 96-99 Burb w/dual air is a pretty direct bolt on.
You'll have to open up the passenger side hole in the main bracket and change the bolt. The hole in the rear steel bracket will have to be opened up or redrilled as well. The plugs are the same, I would highly recommend stepping up to 8 gauge wire or even 6 gauge and run directly to the battery. The belt will have to be about an inch longer.