I've changed the whole roof of the car and taken everything off except the door panels so I know
how to take the lining off.
One thing before we go: you can't get the lining out the car since it isn't foldable and it's not going to fit any of the doors in one piece. The only way is to remove the windshield or to fold it a bit. I folded mine a bit to get it out and took off the windshield to get it back in.
However, to take off the antenna you don't really have to take off anything else but the white plastic covers on both top sides of the boot (the other one having the boot light in it) and the white plastic holders. After that you can pretty much bend it just enough to feel the antenna screw and nut. The antenna comes off just by holding it and loosening the nut. No scratches should appear if you're gentle. Make sure your hands are absolutely clean ALL THE TIME! The lining is a real pain to clean after you have smeared it.
On the other hand taking off the entire lining and laying it on the bottom of the car is an option, too! The things holding it up are:
- door and boot hatch rubber sealing lips
- two white plastic buttons at the back
- white plastic covers on both sides of the boot (to remove these, remove 4 screws and just pull from top)
- white plastic covers on both B-pillars (between doors, to remove these just pull from bottom)
- sun visor brackets (these have 1 screw each, behind a cover plug)
- sun visors (these have 2 screws each, behind covers - the covers are hard to get off, but they do come off with a good pull with a right tool!)
- interior light (this has two screws, you can see them after you take off the light cover)
If I manage to find a decent fin here in Finland (hee-hee

) I might do a tutorial on this.
Oh! And the aerial connector didn't look anything like the one showing in the ebay-link shown earlier in this thread.