I'm having problems removing rear seats on my 540i e39 saloon
i.e not got a clue how to remove them!

Please help i'm pulling my hair out

Yea I know, there all the same. Push in real hard and snatch out.... The front of the rear seat has a pointed fastener that fits in a slot where the front of the seat meets the carpet. Push in and lift real hard, by the way your batt, might be under there........Bill.