I finally got this sorted out by paying $50 to become a full member of the Technology Transplant website. Its amazing how much attention about £30 will buy you!
The trouble is, what with that cost and getting completely stitched up by UK customs we'll be very lucky to even break even on this deal.
On a side note, if you live in the UK and have ever got charged parcelforce's £8 or £13.50 'clearance fee' on top of the customs VAT fee, you might be interested to know that its completely illegal for them to charge you that money. Do a search for information on it on the net. If you just refuse to pay theres nothing they can do about it. They're not about to take you to court over it as they can't afford to have a judgement against them, and its illegal for them to ransom your package for a fee to do a job you never asked them to do. You can even claim back any 'clearance fees' you've paid them in the past if you have a receipt, and they barely even question it.