May be a bit late already, Nobby, but email them at
ticket@lemans.org, phone 00 33 2 43 40 24 75 or 00 33 2 43 40 24 77 or fax them (havn't got the fax no handy - it's on the ACO website) stating your requirements. Give them a first and second choice of tribune. The one you were in this year was T19 Lagache - see map of grandstands at
http://www.swr2002.pwp.blueyonder.co.uk/maps/grandstand.jpgThen you sit around and wait for a couple of months to see what you have been allocated.
Best of luck
Del