Hatch open, closed, where on the hatch: side , middle, where on the seat, Rear Seat up stright or reclined? At the floor level or up higher? With so many variables it might be best, for you, to go to a nearby dealer to get the dimension you really need.
I notice you list your homepage and occupation as, edmunds.com, if you work there maybe someone has that info already on a interior specification sheet supplied my the manufacturer.
Just some thoughts and questions.