I've had no formal training, no one showed me, I'm not an engineer and am probably of only average intelligence. I bought Vance Harlows book, asked questions of the SB gurus and figured it out. It's not as hard as I was lead to believe. The hardest part was initially finding a source for kits and the tools required, most of which I later discovered were not actually needed although nice to have. I've been servicing my Apeks for some years and recently began/learnt to service G250s. I'm glad I took the time to learn, I enjoy doing it and the sense of satisfaction it gives me. It's not for everyone but if so inclined it can be done.