If this helps, here are a couple of angles of the boot in my MG5 with seats fully folded.
Sorry for the grubby canvas liner - it was transferred straight out of the old car.
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There's quite a step up from the lower boot floor to the seat backs. This could be made more uniform by fabricating a riser for the boot floor, as
@thefunkystoat has demonstrated in another thread. This would also have the advantage of allowing a full-size spare wheel - as it comes, there's only room for a space-saver as the wheel well is just 5" / 12.5cm deep.