Sofa bed removal from slide out. Ran into an issue

I think I have the same situation under my sofa/bed.
Please take some measurements of the height of the slide, do this outside. Then measure from the inside ceiling of the slide to the "board the sofa/bed sits on". If the distances are about the same (+- an inch or so) then that board is the bottom of you slid. And you cannot change it.
So like me you're out of luck with a recliner.