Bill is seen holding a Heisler Beer can. Heisler is a fictional beer company created by the prop supplier Independent Studio Services and is featured in several other shows, most prominently in Workaholics, New Girl, and Brooklyn 99; placing these shows withing eachother's universes.
On the boat Ray has no shirt on with what appears to be several hash marks (18 in number) tattoo. As the scene changes and comes back to a view of his shoulder the tattoo is gone.