Being one of the newest types of sets, refurbishment didn't start until late in the programme. First vehicle done was 51843, outshopped in July 1979, after 2 1/2 years in Doncaster following collision damage. The final one was 52081, exactly four years later, and three months after its partner, 52072.
As with most DMUs the refurbishment was carried out in accordance with the BR Director of Industrial Designs Schedule 10. First class seats were reupholstered in a check brown moquette, and the second class in the universal blue/green pattern. Armrests and headrests were re-covered in matching plain vinyl. New orange and ginger carpets were also provided in the first class. First class saloon walls were panelled sand melamine, but second class retained the original pale-green panelling, except if this had been damaged or taken out for asbestos removal. Second class partition walls and doors were resurfaced, or painted blue as appropriate. Fluorescent lighting replaced the tungsten originals. Toilet and guards compartments were also given a facelift, driving cabs repainted and the drivers seat recovered. All surviving vehicles except three trailers were refurbished.
The following images are from an official British Rail photograph album of the refurbished sets.