It dont matter where you enter. Go to a port that is open 24 hours and cross when very busy, and act normal. Dont take any cash that is not hidden. If I had to go I would ride a motorcycle across at Juarez(El Paso). Then its the Baja for me. What in the hell is the peasant life style. You will be a gringo, period. You might try becoming cabana boy, you know the one who delivers drinks. No, just kidding. Try and get a job at a hotel on the coast. Work to get money have someone, wire you money if you need. Lots of money is western unioned into old mexico. I once stayed around Mex City for 2 years, I left TJ with 50 bucks and a beat up motorcycle. Only got arrested once, man they make a mean taco in the joint there. Muy caliente.