If you are staying with the Cleveland, I would recommend you get the Kirk Evans Bulkhead reduction kit. You will get move passenger room and a smaller hump. It provides a new Dog hatch and new interior trim to go with it.
A flat bulkhead was one of the attractions (albeit a minor one) of going with the 4.6. If I stayed with my Cleveland, modified or not, I would go with Kirk's hump reduction.
In any case, I am sure there are stock Dog Hatch covers available (From this forum and keep your eyes open EBay and the POCA forums) particularly from all the people who reduced the hump.
PM me if you wish.