Hi chaps,
Just a update; I finally got the thing running! Got the carbs rebuilt for the princely sum of £30 squid! Lobbed them in attached the fuel tank and after a few turnovers(not apple) and some choke it started! Left it ticking over for a while, and then gave it a bit of throttle: revved up fine. Let it run for about 5 minutes, then gave it some harder revs, revved fine up to 8k then stuttered a bit; tried again after a couple more minutes and it did the same at 10k; left a couple more minutes and it did the same at 12k(bear in mind that the airbox was off at this point).
Could this just be because the airbox was off or that it hasn't been running for a couple of years? Anyway I'm so happy it runs now; just need to get a few thing done to get it through it's MOT!