Update
SHE RUNS!!!
What a day I have had today! Bought a new battery in the week and charged it for 24 hours, plugged it into the bike this morning.... nothing. no electrics still! Then I decided to take another look at Waynus' wiring diagram and remembered that the ignition barrel/lock needed to be earthed. Scraped some paint away, turned the key and I had a working brake light and horn.
Decided to kick it over, no spark!
Whilst I thought about the sparking problem I changed the o-ring which Tufty kindly sent to me in the post. The original one had perished and the new one I had was nearly a perfect fit. I no longer have a leak!
I then decided I would drop the engine (took only a few minutes to do) but scratched the mudguard quite badly!

Then my dad helped with scraping some paint off the bracket the condenser sits on (used a dremel tool for this) and then we put the engine back in. I then spent the next 20mins or so putting the carb, air filter etc back on the bike. Still can't find my plug spanner so put a new plug in the boot and kicked it over... there was a spark.
Then I connected the boot to the plug still in the engine.... and it started... first kick! Runs really well and the throttle doesn't even need adjusting.
I need to do an oil change (might tackle that tomorrow) and I also need to put the chain and chain guard back on the bike.
Good news is that it's running and starts very easily (first kick everytime). Only problem is that my headlight isn't working and I'm not sure why. Does it need to be earthed as well? I might just have it wired up wrong though.
I have a couple of ideas for the bike... might not put decals on it just yet and I also fancy putting a different seat cover on it although I'm not 100% sure about that yet.