Well, I'm calling this (sort of) finished... I screwed it to a bit of scrap MDF as a temporary measure to run it, and much to my surprise it started on the third kick. However, it was 'hunting' badly and after playing with the governor setting with no real improvement I called it a day. Yesterday I had a closer look at the carb and checked the manual re: setting and discovered that the mixture screw is missing! Looking at the 'before' photos it was missing when I got the engine. I have emailed Meteens so hopefully I will be able to get it running properly. If so I will try to post up a video.