Welcome to another LM virgin approaching deflowering. A couple of other nuggets of info.
1) Luggage carrying capacity in your vehicle is not necessary unless you want to take frame tent, swimming pool, gazebo, satellite telly and other sundries. For me the boot of my MGA carries everything I need to fall apart for a week with a mate.
2) Aside from watching illicitly on the Mulsanne (which you can also do legally over the fence in the garden of the cafe at Hunaudieres), remember that a good 2/3rds of the circuit is on public roads, which are open outside of the qualifying and race times. Thursday afternoon and Friday morning are good times, although after this year, the Friday morning is now more restricted with the old favourite of the mulsanne to indianapolis section (long favoured by the TVR and Lotus 7 brigade) closed off by the gendarmes.
Mark