How to ship a car hood from Boston -> Minnesota?

I sold the hood from my old Corvette on eBay. The guy that bought it lives in Minnesota and I'm outside of Boston. The hood is fiberglass and has some curves to it, so it is going to need crated to protect it during shipment. Also, it's about 6 feet wide and 6 feet long, and about 2 feet high when laid on the ground. A real PITA to ship.

I have used freightquote.com to get some prices and the quotes range from $250-550 depending on what I am putting in for the weight (I am guessing 200lbs crated).

Anyone have any idea for a cheaper way? Its too big to go DHL or UPS or FedEx. The guy only paid $420 for the hood and while I do feel bad if the shipping is crazy, I also want to get this thing sold and not have to relist it!

Any ideas on the cheapest/easiest way to ship a 80"x80"x24" (after crating) 150lb package from Boston->Minn, please let me know!