Been on the phone to admiral all afternoon getting insurance quote, they have given me 2 prices £612.30 for tinted rear windows, optional alloy wheels, cruise control, external decorative modification (vinyl roof). And a price of £650.62 to also include induction kit, exhaust system including manifold and a remap as long as the total BHP increase does not exceed 25% otherwise they wont cover.
Those prices are for a male, 22 years old, 3 years NCB, clean license, no crashes within last 3 years, with a Gloucester postcode being kept in a public access car park. However it is on a multicar policy so saved about £80.