I have a friend that just bought a 47' Excalibur and the doesn't like the exhaust drone. It has the exhaust leaving the sides of the boat at the water line. I think it has "exhaust chambers" built into the fiberglass?? Anyway, I was wondering if he could switch over to exhaust through the hub. If yes, do the "horns" for a Bravo 1 fit the Bravo 3? Thanks for your help.

Yes, the Y-Pipe is the same regardless of the drive. The Y-Pipe connects to the transom assembly not the drive.