It's very easy to remove the rear seat, allowing access to the fuel sender unit and seatbelt anchors.
See also Removing Front Seats.
At the front of the seat where the seat meets the carpet you will find 2 tabs with a plastic covers. There is a screw attaching these to the car's floor. Undo these screws making sure not to lose their plastic covers.
There is a 3rd metal tab at the back of the seat. Slide the seat gently towards the front of the car to pull this tab away from where it is anchored (this tab is not held in with any screws or bolts).
That's it. You may now remove the seat, revealing the access port for the fuel sender unit/lifter pump and the seatbelt anchors.
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