Ok so I overreacted! The oil leak was actually a petrol leak. I pulled the tank off and used thread sealer on the taps and that seems to have fixed that. Jimi came round while I was doing that and so when the tank was back on we kicked it over. Started first kick again! Jimi adjusted the throttle cable and pretty quickly had it idling at just over 500rpm. Pretty sweet!
I noticed a funny noise in the primary though and when we inspected it noticed that the rotor, which sticks out further now, had hit and destroyed the timing marker that's attached to the primary cover. Bugger. Will look into that, and recess the rotor by whatever we need to to get that clear when I get the new one.
Although, by pushing the rotor out more we're getting the full 70 pounds on the nut onto it. If it's not spaced out like this will it torque up properly?