Do you have anything under the plywood? Looks like regular 2 wide pallet rack. Unless you have steel under the ply, i would put 2 pallets on there. Just screw blocks under them so they can't slide, and lay the plyboard on them.
Just one engine started to buckle the 3/4" plywood. Not enough support underneath and I don't have time to mess with it, so I'm just going to arrange them on the floor and get the cars in, then think about it for a while....
The shelves are actually a foot depth too much and I would rather not waste that space...