OP I have a suggestion...RUN! If you are a fit guy like you said in your OP then run away. Once you realized he was drunk why didn't you book. It's not like he had a weapon and you were worried about getting shot in the back.
It might seem stupid and cowardly but you could have just turned and ran away from him, you had a whole parking lot to run him til he puked.
Big fat guys run out of steam pretty fast. Also the running would create space and make it clear to an arresting officer what was taking place. I you ran and they chased then you really would have established "fear for your life".