There are 3, 14-19 Bellancas that I know of with IO-470s. N6RJ I think was the first one and the owner,(maybe not the original owner) told me that he didnt get the weight increase of a 14-19-2 and they took away the utility status for it. The next one (that I know of) was the late Drew Petersons plane that I think is still owned by a club member. I believe he took the whole FWF off of a 14-19-3A and bolted it up. No telling how he got it approved. The next one is a Canadian plane that they developed a multiple STC for, but at a very expensive price. From memory I think they used a Viking motor mount which is 4 or 5 inches longer than a -3 and put a 3 bladed prop. It also has the pointy Viking spinner on it. I would have thought it would be ugly with that, but I have seen photos and it really does look sleek. One of our members seriously looked into doing it, but changed his mind over price and the 50lbs of lead that was to go into the tail. That longer mount and 3 bladed prop must have made a serious envelope issue. If you google Bellanca photos you can find the bright yellow Cruisemaster and look carefully at the length of the nose and the odd spinner. Great looking plane. I dont know how difficult it would be to get approval for the increase in HP that is done to O-470s without any weight gain or, I have heard that there is no external change to the engine at all. I would look into that before spending huge amounts of time and money to make changes that might never get approved. I think (guess) that the increase in HP would have a better chance of approval. Just another of my 2 cents worth. _____Grant.