It may depend on the model. IIRC, on a 123, there's a screw or two, or maybe small bolts to free the seat back, and then you just pull the bottom out since it's held in with clips. It's been a year or two since I've done this, so I may be forgetting something.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.