Luke no one can just tell you what the original colors were in just a single post as there were hundreds dependant upon theater of war, which war, which nationality it served and a lot of other factors. Its a terribly complex subject. I would suggest you search 'colors and markings' specifically in the UK as there will be lots of sources. Also you could search on 'Bob Bankas Scale model Research' which is one of the largest scale documentation supplers in the world. However this is a US based outfit and there is sure to be similar outfits in the UK since colors and markings along with Registration tracking is a distinctly popular UK hobby.

Now the seller specifically stated this airplane is setup only for fixed gear and at this stage cutting open the wing is going to be major surgery and problamatical for someone with no building experiance. The key for this airplane being rather small for that size engine will be keeping weight at an absolute minimum. Not only go light on the paint but everywhere else as well.

I am compelled to reiterate if you are tempted to fly that airplane untill you have considerable experiance under your belt then that nice airplane will end up in a pile of foam and glass shards on the paddock upon its maiden flight. Finish it, admire it, and hang it up untill you have that experiance.

John