I have a friend who builds a lot of XS650 Yamaha twin racing motors and then ships them across the country. His method of shipping motors via UPS/Fed Ex is to throw some padding in the bottom of a large plastic garbage can, set the motor down inside and bolt the lid down with many bolts around the edge of the lid.
I thought this was pure genius. Comes with two built in handles that helps the delivery guy manhandle them and it is a cheap, secure, water resistant container. FWIW. ;-T