i run an engine test department for a large supplier of fuel injection equipment to the commercial vehicle trade, we dont have any openings at the moment, (would be nice to get another technician, but oh well) but you could sign up with an agency likle matchtech that supply contractors to r&d sites such as millbrook and ricardo

with a little training you could command £17-18 an hour as a technician on a rolling contract, if you were looking at permanent staff at a technical centre, you'd be looking at between £22 and 27k.