grufflehead
First Post
Okay, here's some thoughts.
<snip useful stuff>
Additionally, there's no such skill as Mechanics (Jump Drive). You -have- to have Engineering, because that skill is required to plot the jump, as well as maintain and repair the drive.
According to my 3rd Ed GURPS book, there are specialisations of Mechanics for Spaceship Drive AND Starship Drive. The specialisations for Engineer are much more 'generic' e.g. Vehicles, Plumbing, Electrical.
By that line of reasoning (and you're own explanation), Mechanic is what I want as he has no 'formal education' per se plus the skills are much more relevant.
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Now, as for the ship...
I suggest that you and I link our backgrounds somehow....
<more snippage>
OK, no problem with previous association. I had in mind something more like: your character has come into possession of an old barely working ship, possibly salvaged as per your idea. It plays up and he is forced to land on planet X. While scratching his head as to what's wrong with it, he encounters my character who takes one look at it and correctly diagnoses the problem ('ah, your atmosphere intake inverter is likely clogged. Here, I've got something that'll sort it out for you). So impressed, you offer me a job

Does that sound a workable jumping off point?