Engine business can be very frustrating. I always said you can build the best engine in the work but some idiot puts his junk carb and distributor on it with some "spin to win timing" and you'll shortly have a pile of scrap. I got out of it over 10 years ago now at the advice of a 70 year old guy I was working with. Wouldn't mind adding some equipment to my garage just to do some hobby/side work. I don't regret switching careers. I do miss it at times though, when I gotta pay for some machine work that I could have done better myself.