Maybe they inadvertantly messed up my order? Am I getting more stuff? Maybe they're sending me two . . . or . . who knows.

I have not ordered much from Tower so I cannot comment one way or the other but getting two of what you ordered.... this summer I orderd some rock sliders for my Xterra. They weigh about 100 pounds and cost about $500. Like you I watched for the tracking numbers and tracked it from Texas to my home in Oregon and I was excited when they got delivered, only to have two laters another set arrive that I did not order or pay for.