GT trim
Sounds like an easy fool proof way to go
Make sure the box is rigid, plastic drain tubing works well.
I had a guy from CA ship me some 67 dart rocker trim. He strapped it to a 1x4 and padded the heck out of the outside.
When the US PO delivered it there was a 30deg bend in the board and trim 2 feet from one end. Like someone set it between two boxes and jumped on it.
IMHO someone had to purposefully do it.
Other of the same was shipped inside 4" PVC drain line and was perfect on delivery.
Recently I bought some parts from a Fabo member and my daughter picked them up.
Made up a box and shipped it to her.
In the box is a gauge cluster a radio a heater control and a radio bezel.
Before she shipped it back!