you need to tell them everything buddy as anything not as standard and they'l prob try and get out of paying if a claim is placed!!! companies like direct line admiral etc will normally sting you quite bad for the smallest of mod's as they dont specilise in modified cars, your best trying to get with a company like Aplan, sky or chris knott as these specilise in modified cars, im covered with Aplan and it cost me another £30 quid over what admiral wanted for the car as standard and i have a massive mod list