If you’re looking for the cheapest way to ride the PATH, it isn’t with the new tap-and-go credit card entry … yet. PATH riders still should use their SmartLink cards for now if they want to pay a $2.60 fare since the current TAPP fare is the standard $2.75. But once the TAPP program is fully implemented, the Port Authority will begin offering the same discounts for TAPP riders as SmartLink riders, according to the Port Authority of New York and New Jersey, which operates the rail system that runs between Manhattan and Jersey City, Hoboken, Harrison and Newark. And though SmartLink and MetroCar…