I'd only been 'way south' once before when I flew into Mexico City. Well, that part of Mexico hasn't changed. After a while you get used to the smell of the exhaust, but again after a day I had a dull sinus headache again. Anyway, immediate change in driving habits. Anybody parks anywhere they want.
Traffic is dense as sardines and rolling mere inches from each other.
Lane split, and Do Not make eye contact. Luckily, I kept my eyes on the road. I stopped, waiting to at least be asked a question. After about 2 minutes of no one giving me a second glance, I rode off somehow expecting to be chased at any minute. Then I remembered I was supposed to get a vehicle permit 'after I crossed the border', so I turned around on a side street and headed back to the border.