Okay, now I may be cheating, but a person should use the tools available to them, right?
Anyway, related to a project I'm working on, I've just remembered that there aren't just bitmap line drawings available, but actual vector CAD files.
Yeah, it may feel like I'm cheating, but I'm also up against a deadline. There's plenty of manual work to do even with those files, so I'm still putting in my time...