Bill,
The fuselage I bought from a guy was built as a 9 and I converted it to a 9A. You will need a new motor mount and will be doing some work on the cowl, but it is not a difficult change to make. You will curse the gear mounts and getting them installed, but it is possible and you will be fine.
You will have to decide if you want to take the support pipe for the rear wheel out or just leave it. I decided to leave mine in because it will be about as bad as the latest SB's for the 7 to get it out!
The fuel and brake lines get changed and if you don't have steps, you will have to put them in.
Outside of the wing bolts being difficult to get in because of the gear mounts, it was actually enjoyable. I didn't really mind the tail wheel, but it is a deal breaker as far as my wife was concerned. I think I will build a Kitfox after I get my 9A done!