Use the same people that ship PINBALL MACHINES across the USA Every single Day. I use to use Bettman Logistics but their website no longer works. They would come to my house and blanket wrap/Clear wrap my machines and take them anywhere. Not sure if these places have boxes to use but they definitely have pallets. I shipped 50+ machines with no incidents. The PINBALL hobby is pretty huge so shouldnt be too hard for you to see who everybody is using on the internet these days. Just a thought.
Packing & Shipping Large/Heavy Speakers
I have a pair of Legacy Whisper XDS's I'm wanting to sell. They measure 63x17x13 and probably weigh about 200lbs (or more), so extremely large. Most of the advice I've read is simply to crate them on a pallet and then ship freight; but how to go about that? I know for freight shipping there are websites to get quotes, but it's really the packing aspect I'm concerned about having never tried to pack anything this large.