TenTec used to, or maybe still does, use the foam method. But as I
remember it, they filled the box just halfway, then set the plastic
wrapped rigs in the foam, covered it and the lower foam layer and upper
sides of the box with plastic film, and poured in the top foam layer.
Opened like a clam shell, easy to get out.

My last employer (Daytron World Communications)
used this method to ship their radios. Very low
damage rate.

73, John - K6QQ