x2 for Greyhound.
It is not the best service but it is pretty cheap. I had 2 front 1951 F1 truck fenders and 2 running boards shipped for a fraction of the cost from Cali to MI.
I did have a hangup in Las Vegas due to people coming back and their luggage taking priority over my parts. Tracking is a bit of a cluster because it is only as good as the last person who entered it in the system. I found myself following up with Greyhound quite a few times to get an update. Some of the shipping locations would stay stuck in place XYZ for days then all of the sudden, it would be 3 states closer. The person unloading/loading the bus would properly load it but not put it in the system.
The only big hiccup I had was when one box arrived to the Pontiac depot, no emails/calls etc. I waited a few days and called Greyhound, they said it arrived 2 days ago. I get there and the guy behind the desk told me there is some sort of storage fee after day 1 or 2 but he would waive it. Apparently, the person receiving the package is responsible for contacting them to avoid this.