I wouldn't bother to tell them. Never seen or heard of anyone having an accident and the assessor using a laptop to look at the software on the ecu! I think they care more about wheels, brakes, suspension etc etc than whats on the ecu. It would be very difficult to see the map even if they did, remember a map it a tweek on timing and fueling etc in the old days it was called a tune up.... I would have no issues failing to tell the insurance company that my standard car has been tuned up that now adays gets a fancy name like uprev..