I think you will find the flaps are gummed up, the strip down didn't really throw up any surprises for me, although you need to be firm when removing the lower intake, the injectors are quite tight on the o rings. just gentle and firm wiggling got me there. A good workshop manual will help.
shout up if you get stuck - I found it really satisfying doing 100's of £ worth of work for virtually nothing!
good luck