I use and recommend Fedex Ground. I use Mercury factory pallet boxes that the dealer is glad to avoid paying tipping fees to get rid of. If you use a box, plastic drink bottles make good filler.
Deliver to the carrier if possible. Forward Air will accept motors strapped to a pallet. You have to take it to their terminal, usually at the airport. Fastenall is another shipper but last time I checked their rate was about the highest.
And, yes, freight rates have gone way up in the last few years.
Goof luck. JW in Dixie