Cheers bikerboy - I'll look into that. Currently, the ATD is with my mate who's making the rivets (plus a spare set) for me. May never need them but it makes sense to me. I've looked at Priory Magnetos and it seems Andrew is not taking new business until July (from the website - please correct me if I'm wrong). The kit Andy offers is well priced, will probably cost me more than that to get them made but, hey, the guy's going to repair the ATD and show me how to time the beast up (fix and tutorial all in one).
UPDATE: Have removed oil tank and cleaned out 3 times with brake cleaner, cleaned the feed and return pipes. Removed sump plate and gauze and OH MY GOD, the crap that was in there.
Must have been pretty much all of the shredded teeth, some general crap, and the remains of a small antelope.
Cleaned all that off with brake cleaner and replaced. All timing side is as clean as I can get it (tips for removing old gaskets and liquid gasket please). I used brake cleaner (great stuff) and a very sharp razor blade (at right angles to the case!!) - seemed to work ok.
After the timing's sorted, plan to put a couple of litres of my cheapish oil in, give it a quick run, and repeat once more before filling it up as normal and going for a hell of a run. What d'you reckon?