Combine the garlic salt and Tajín in a small, shallow dish in an even layer. Rub the rim of a cocktail glass with one of the juiced lime wedges, and dip the glass rim into the dish to create a salt rim. Add ice to the cocktail glass. In a cocktail shaker, combine lime juice, spicy tomato juice, hot sauce, Worcestershire sauce, jalapeño juice, black pepper and a pinch of salt. Shake vigorously, pour into cocktail glass, add 2-3 slices of jalapeño and top with Mexican beer. Use the remaining beer to top off cocktail while drinking.