The seller said he took the radiator to the carrier and asked the person behind the counter if the packaging was okay.
The radiator had to be returned to the carrier, for analysis, so I could get a refund. No option to buy back.
I learned from this that shipping heavy items requires some experience and thought when it comes to packaging.

"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."