The Lotus Grand Tourers

Assuming the same as Richards, undo 2 screws at the bottom near the carpet edge.
Then pull up and out on the rear edge that abuts the back rest.
Once it's up and clear of the back rest, push the whole seat squab towards the rear of the car. It's just a hook tab. Seat base is now out.
The first time you do it, it seems your bending the seat base badly and it feels quite brutal, but the base is very compliant.
Tony

What Tony said.

The pictures below show the pretty basic slot on the car, and the tab on the seat base, just made of bent aluminium riveted in place.

That's brilliant thank you so much both

Kerry