It bolts onto the chassis where the seat backs bolt and ideally needs 3 pop rivets put in it too (this is how it was fitted in my 6. Can upload a pic if needed.
I no longer use isofix so don't need it any more. Will fit and 3 door and probably any 5 door (although can't be certain about the 5 doors).
£20 collected, cheers
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Ex Astor 6 ownerAlso an Ex owner of a Bianca 6
Now an ex owner of a 2005 9-3 2.0T 210bhp Aero Swedish Saloon thing!! Soon to be 250bhp....
Now driving Mk5 Golf GTTdi, mile muncher
But still live for the 306