I think bodykits are a grey area when it comes to the options list, not heard of anyone managing to get a bodykit insured as OEM before that's for sure!
I think a lot of the telephone staff need educating a bit more in modifications when they are the ones deciding how much extra to charge you for them. I remember trying to explain an ECU reflash to Liverpool Victoria and had to give up after 15 minutes as it got me nowhere. Far better now with the likes of Sky and Chris Knott, very refreshing when they know exactly what you are talking about and made a much more informed decision based upon that info!