The note can be found at Camden Park, pinned to the wall next to a fusion generator underneath the entrance to the Widowmaker.
I've got a great idea to haze Hal on his first day. Let's just say I stole a bunch of laxatives off the old man last night. I'm thinking those, plus Chow Line, equals nightmare bathroom duty for our old pal. To top it off, it'll make Newman lose his mind. He'll be neck deep in customer complaints. Get him back for docking our pay over stupid "infractions."