Great idea Ray , it looks good !
Having built crates to ship Cobra kits I can say that you're actually on target . The entire floor of the crate is actually a large pallet that's completely bolted together (no nails) . The frame would be bolted to the pallet and then the body would be bolted down to the frame . The crate was then built around the body and boxes of parts would be packed in and around the body , probably some tie down straps added , and the crate would be shipped by a private carrier such as Reliable transport . No way it would survive going commercial freight .