Maersk have taken on engine cadets with a restricted eng1. Like myself, I was unable to pass the Ishihara plates which is the test with numbers and coloured dots, however the MCA will issue you with an eng1 if you are able to pass the farnsworth d-15 test or the city university test. You can do these colour tests at the optometry department at the Glasgow Caledonian university. All you have to do is phone them up and book am appointment. Where you aware of these tests?
Hope this helps