Use TForce Freight (UPS Freight) - double boxed and on pallet(s). I just received (in IL) a 500lb Yamaha piano via TForce from the piano dealer (shipper) in MD in perfect condition (box and contents) - double boxed on pallet.
The dealer (shipper) noted he’d used them for many years with only one issue, which they resolved quickly. As noted (above) they use fork lifts to handle the packages and are skilled in handling freight in contrast to routine boxes (lighter weight) of the typical FedEx / UPS shipment.