Hi Rossco,
Greenlight do offer track cover via some of our schemes, but we would have to be covering the vehicle under an annual performance/modified car policy to be able to add track cover, which from what you mention looks as though you've got the standard road aspect covered.
If your'e looking for stand alone trackday cover, competition car Insurance or Everitt Boles (
http://www.moris.co.uk/) would be able to help.
Kind regards
Tony