Preston do one too but the problem will be fixing it to your box.
The sliding footplates bolt to the underside of the frame.
On a matchbox the frame is in the middle of the box, ie. drawers and seat above the frame and base unit below the frame.
So, the base unit will be in the way. You have to have a box with the frame at the bottom. You cant just remove the base unit either, because unless you have VERY short legs, your knees will be up to your ears.