Greyhound is best. Just wrap with cardboard and tape it up. It is a great way to ship doors and fenders
Like it was said above. You ship and receive at a bus station. So, you need to be close to one. They also need a phone number to call when it arrives. They will hold the parcel for three days - after that there will be a holding charge. I think it was a buck a day, here in Dallas.
Best of luck