you need to remove the interior light and the surrouding cover...the ariel co ax will go into a metal cover(tin?)..this needs to be prised off and will uncover a small nut this secures the ariel mount..you might be best to ask for help to hold the mount outside as you undo it or it can spin round and mark paintwork..like i did....you might be best to get an indoor ariel,you can get powered one that connects to interior light supply and sticks to inside windscreen...
craig, March 2007