Spot on and the club don't seem to make much effort to highlight the options regarding 'official' parking open to away fans on their site.
The simple answer is to go by train. Leave as early as possible and, by the time you depart your London Terminal for the second half of your journey, crack open the port and Stilton. Then spend ages finding the only pub in town that serves good beer and doesn't have a regular crew of psychopathic knifemen at the bar and stay there till 2.45. Trust me, you won't give a shit about parking after that.
Oh hang on, aren't you the bloke who thinks you're a planet killing Jeremy Clarkson if you take the hatchback shopping?