In message
<584ad53bdef024ec0f851084ac8b48dd@localhost.talkaboutautos.com>,
Billywizz <billc@dikbearings.co.uk> writes

Remove the interior light, leave it hanging, it'll be OK. Unscrew the
sunroof motor (3 screws), leave it hanging too. There is a metal cover
over the underside of the aerial, this just pulls off. Then it's just a
case of unscrewing the old aerial and fitting the new one. I seem to
recall re-using the original nut, not sure why, but might have been
something to do with the aerial wire.

When fitting the new aerial, ensure a watertight seal where it meets the
roof, I used silicone sealer on the underside of the aerial base,
allowing the excess to squeeze out as I tightened the nut.

Be careful not to allow the sunroof or its motor to move/ turn while
it's off, so that the gear remain correctly meshed.

HTH (and good luck!!)