The last I had heard about Tuna, was he was working on a HUGE dairy farm in the New England area, supporter of the Green Party and would fondly talk about his time with George.

The movie kinda kept up what happened with Tuna. One day in the pot smuggling days, they all did acid. The last George saw of Tuna, he was walking down some railroad tracks and that was it. Tuna just kinda vanished. Some time went by (a few years if I remember) and George ran into Tuna back home, Tuna acted like nothing happened and that was that