This is a hobby/sport. My definition of a hobby is: An activity one participates in without expectation of any return on investment except the pleasure of doing it. If we are worried about the R-O-I, then we need to find another activity. Hobby money is funded from disposable income after(sometimes) the bills are paid. The pleasure of achievement is enough. The ingenuity involved in solving the problem is reward enough. If something doesn't come out exactly like a production model, who cares. If the conversion works at all, it is a success for the converter.