Lots and lots - crates or pallets...
On a pallet they typically like it plastic-wrapped. (U-Haul sells the green stuff on rolls that I go ape-**** with...)
Crates are harder to produce, but they can stack them, so it's typocally cheaper...
Either way - certify it clean and free of oil or fluids (and make sure that it is so...)
Try BAX Global - 1800-CAL-LBAX.