DRS currently have a pair of Class 57s on loan to Colas Rail. They carry Colas Rail branding stickers.
I had a Bachmann Class 57 in stock and so had a bash at this relatively simple conversion. Firstly the running number was removed with a little T-Cut on a cotton bud and replacements applied from Lancaster City Models
(they stock the full range of DRS decals for all classes).
I applied the Colas Rail vinyls, which are available from Precision Labels
, masked off the glazing and gave the model body a coat of stain varnish.
I then went on to give it a light weathering.