I'll also give Fastenal the thumbs up. I sold a Zephyr trans, almost 3 yrs ago and the quote, was less than 1/2 what Fedex was but, the pandemic was full on and Fastenal had shut down many of their stores. It was to go to SD from here in OR, I would have had to drive 80 miles to a depot and the SD store was closed, so, it could only go to the LA area. So, I wound up having to Fedex. It cost the guy, almost as much as the trans.
On Fastenal stuff, it's cheaper if you crate it so, it can be stacked.
I recently found another shipper called OnTrac Shipping. I got it from a tire supplier, I used last month. He said they are the best for the large tires, he ships. They specialize in shipping larger items but, I haven't used them yet:
https://www.ontrac.com/services.asp