Beware fitters are often called "engineers" up here so don't rule out those jobs either.
Qualification wise I've been told minimum time served apprenticeship,plenty of experience and usually compex/survival but some places may accept you without compex and train you on the job,although the problem being that there's a lot out there that do have it which puts them a step ahead of you etc.
The agency boy told me my level of knowledge and experience exceeded anyone he'd put offshore that month but because;
A) I wasn't living locally
B)had no survivex
C)no compex
D)no offshore experience

That a+b+c+d= no fucking chance!!