I love to build things also, i.e. a house, outbuildings, a couple of boats, etc., but I am not a machinist. I was a database programmer/analyst by trade. Dad of course was the expert machinist, but he passed away in 2009 :( I have a basic working knowledge of most of Dad’s projects, but I cannot answer real technical questions.
Fortunately, Dad's plans are very detailed and complete, and any experienced builder (and most novices) should have no trouble at all. Occasionally a builder may have a question or may not completely understand something, and if I cannot answer your question, perhaps someone else can, as hundreds of these engines have been built - perhaps thousands (I see them running at the shows all the time).
Search our blog by engine name and I may be able to put you in contact with someone who has successfully built the engine you are working on.
Also, there are lots of users in the big forums (www.homemodelenginemachinist.com and www.hobby-machinist.com) who have built a lot of Dads projects also who can assist with technical questions. Also, check out youtube as many builders make and post videos of their running engines. Most will be happy to answer any questions you may have.