Ok, I know there is a How To on this already, but it’s kind of crappy and it’s a little different on the 05+ foci. I had to replace mine today because my dad broke mine off yesterday brushing off the snow. So here it goes:
T25 torx bit or screwdriver
Regular Flat screwdriver (preferably smaller)
Phillips #2 bit or screwdriver
New Antenna base (~$12 at the stealership)
Step 1: Pop out the dome light and disconnect it.
To do this, just take your flat head and pry it out starting in the front. It Comes out very easily. Then remove the two plugs from it, they just pull off.
Step 2: Remove the Torx Screw
Up inside behind the dome light, you will see a torx screw and what looks like a wire attached to it. Unscrew this and the antenna base will be free.
Note: Be careful with this screw, there is a washer on it that you can't loose.
Step 3: Clean area and have a helper hold the new base in place.
You will need to have someone hold the new base in place to keep it aligned while you screw the torx screw back in.
Note: On mine, there is a scuff around the perimeter from the old one, this pic makes it look worse than it is, and I will be waxing it when the weather is nicer.
Step 4: Re-install the screw with the washer on it.
For me, this was the hardest part. It is on a funny angle and I ended up taking the whole over head console off to get better access. It is only 5 Phillips screws and it just pulls down off of there. Be sure not to over-tighten the screws!
Note: There is also a plastic clip kind of thing that helps align the base, mine came out when I was drying the area around it. Here is a pic of it; it just clips back in through the roof.
Step 5: Reverse the steps to take down the OHC and dome light and you're finished!
This took me about 20 mins tops and that was including the time to stop and take pics for this How To.
Good luck and I have a few more detailed pics of some things if anyone is confused about something.