+! on the pallete. you can make this easily out of scrap wood - just make the thing a uniform shape and make it strong. I probably "overkilled" it last time i sent one...but... it got there safely.
I built a little pallete. I built a wood frame and used the engine mount bolt holes to bolt the thing in place (with long threaded studs. I wrapped the engine tightly in thick plastic and then decided to double protect the fins. I made an "inner box out of heavy cardboard and fitted that closely around the top-end (covered as I said with heavy clear plastic.) I then used a couple cans of that nasty/toxic smelling expanding gap-filling foam, smushing it into place by pressing on the cardboard to which it eventually adhered. It hardened and I then made a heavy corrugated box out of sections to go around the whole shebang. I felt pretty sure that they could drop it off the forklift from 8' and the engine would have been fine, but luckily, they didn't test that.
