Thanks for posting the video Nigel. That looked like perfect snow to fly off of!!
Regarding the elevator servo installation, it is a tight fit but entirely workable. But as Kingsflyer said, part of the fun is doing things your own way and if that works for you then great. It certainly frees up space inside the nacelle!
I have built two kits with the servo inside per the instructions. Perhaps on the next one I'll try mounting it externally.