The "fin" antenna on my beloved '01 E320 wagon appears to have a broken mast(?) and a rotted base rubber seal. Looking to replace it I found a repair kit on ebay that comes with such seal and what it appears to be a replacement mast.

First question, can I work on this from the top of the car or do I need to remove the headliner?

Second question, is the mast replaceble or does the kit includes only a cover to the existing mast? In that case is wrthless as my mast is broken.

Thanks for any help. If this has been covered before I apologize, please point in the right.

Thanks