Graham,
That is a really nice looking OK, next time you are up there it wouldn't hurt to put a piece of wood under the wheels to get it up off the ground to help perserve the wheels. If your lucky by the time you get back there the diesel will have worked it's magic and it will be loose and you will possibly hear it run!!
Gary, I really don't think I should show you this as it may compleatly discourage you from ever possibly owning a Wallis but I feel you should at least be warned of what can go wrong just so we can keep you arround a couple more years....
This is the perfect example to show what happens when you have too much advance on your magneto. John has been working with crank tractors for over 20 years so kickback is not new to him, but just a reminder of what can happen....
Click link below
http://www.youtube.com/watch?v=PYOjaqWYDJI
Joe