Re: Shipping cradle/trailer
Welcome to CF!
a boat via ship, it's not uncommon for the shippers to weld the jackstands supporting the boat to the deck
. This, in addition to securing them via more normal methods. As well as securing the boat in place via tie downs (using various methods & materials for this). And this is so that the vessel can't move around, plus it assists in keeping her vertical.
The Uncommon Thing, The Hard Thing, The Important Thing (in Life): Making Promises to Yourself, And Keeping Them.