 They were converted to further parcels coaches as a stopgap measure while 10CM and the repaired 3CM were busy with various electrification works, and so the conversions were minimised.Instead of a full rebuild, the seats were removed and a walkway down the centre was cut between all the compartment partitions, but the cars did not have the sides replaced, and they stayed red.They were recoded to 15CM (1964) and 14CM (1963).