It can't have been that difficult. I'd have relabelled everything for convenience though. But a diesel engine is a diesel engine, a valve is a valve and so on. You get training to work on a specific type of boat/plane/tank whatever, you get re-trained to work on another model the basics don't change.
Beside, every single one of us uses technical equipment every day that has been designed by people from another country - I'm writing this on a laptop designed in Japan, built in China, running an OS fom the USA with the GUI set to a non-english language running a webbrowser from scandinavia right now and I'm doing just fine. Oh, and the electricity it runs on is probably imported from France.