Don't know if you've seen it already, but I found a very extensive walkaround video of a Spit at Duxford which also explains many of the features in depth:
Spitfire Mk5B LF Walk-Around With Pilot David Petters | IWM RAF Duxford - YouTube
This playlist is also an excellent in-depth resource, featuring the same aircraft (G-MKVB) as above:
Spitfire Mk V – An Overview - YouTube