Marcone...you have a lot more energy than I have. I would just take the engine you have, make it the best it can be and call it done. I am pulling for you, but wow, what a lot of work and engineering to try and get where you are going. ...and in the winter where you live? I don't know how you do it. It's a rather chilly 85 here today, so I'm thinking about staying in by the heater.
I know it won't take long to pull the engine but putting back what you are talking about is going to take a lot of money and a enourmous amount of time. Good luck to you my friend and let us know how it's going.