Gents, thanks for info. For the IVA I had planned on temporalily locating the rear fog in a more central location and away from the rear light and then fit back into the body recess later. However, 40 Buds idea to rotate the rear light is a blinder. It means that there would be a 100mm gap now. I checked this against the IVA Manual, and this specifies a requirement of "100mm min from the rear stop light".
Thanks