An out-of-town couple face narcotics charges after they were caught with a rolling meth lab in the parking lot of Centertown’s Dollar General.The suspects, Crystal Gayle Parton, 30, of Murfreesboro and Jean-Luc Keller, 21, of Tullahoma, were both bound to the grand jury by General Sessions Judge Bill Locke on charges of possession of drugs and promoting the manufacture of meth. Parton was also bound on the charge of driving on a revoked license.Their charges come after sheriff’s deputy Brad Myers noticed a car parked in the parking lot of Dollar General in Centertown. Drawing his attention was the fact the car was parked there after store hours and because its interior light was on.Upon approaching the vehicle to speak with its occupants, Myers said he saw components of a meth lab placed where they could easily be seen.“In the back seat, in plain view, was aluminum foil and an open bag with a bottle of iodine,” Myers said, noting he was then allowed to search the vehicle.