Back in my Air force days, gunnies overhauled ejection seats. They come under the umbrella of avionics technicians these days I think. Over the years the discussion has come up in regards to ex military aircraft on the civilian register and their ejection seats being disabled. This has been done because of CASA's stupid regulations. People have died who may have been alive today if the ejection seats were armed.
Here is an idea CASA, potential lives could be saved if RAAF qualified airman could be allowed to overhaul ejection seats on civilian registered jets as long as they have the right equipment and did it on their own time. Ya never know, a life maybe saved.