Well, the fact that you were able to work on an EM and get it working without ever seeing one before shows you have more skill and talent than most. Aside from a lot of the EM owners here on Pinside, there are not a whole lot of people out there who know how to work on these. If you enjoy it that much and have had success, then I would suggest getting another here and there and keeping them alive. You can usually pick up non-working EM pins fairly cheap. Fix them, play them for a bit and then sell them, using the money for the next pin. Seems like a win-win hobby for you. Once you get really comfortable working on them, I am sure your skill will be in some demand in your area just due to the lack of people available to work on these machines.

Awesome job bringing this one back to life and kudos to you for returning it after fixing it!! I am sure they will call you to fix it in the future and who knows, they may gift it to you when they are done with it someday. Good karma will come your way for what you did.