Man, only an idiot wouldn't know what that is.
That said, I have no idea what it did. It's not factory, and I sat here and looked at it for five minutes and tried to decide WHAT you could do with it. Wet locker hanger? I dunno. If you can't find a use for it, cut it out. Frank and the gang didn't put it there.
VERY nice engine though. Unless there is just something wrong with it, you will be more than thrilled with your acquisition. That thing will be the pride of the boat.
I've said this before, but never once in my life, car, truck, plane, boat, anything, have I ever heard, "You know, I really wish I had a little less horsepower".