Some low life snapped my aerial last night, leaving the threads from the aerial snapped off in the base so now I need to replace both the base and aerial.... the trouble is how do I remove this......

so I can remove this......

I take it I need to remove the interior trim to get under the roof lining so I can remove the nut on the base ??

so I can remove this......

I take it I need to remove the interior trim to get under the roof lining so I can remove the nut on the base ??