I looked at everything from tranport companies (all of which had to find a comntract hauler due to the size), light/partial load flatbeds, to rail transport through BN&SF. for a 980 mile trip the lowest I found from Washington to Southern CA was 1,400, highest was over 4,000 door to door.
I had some luck with folks at the tow411.com forums, there are some outfits that will occasionaly do random long hauls, pric3e according to milage, but some of em were fairly reasonable.

1956 GMC 370 dump " 'Tater "
1970 VW Volksrod "the Black Bomber"
2007 Chevy Avalanche
2020 Jeep Cherokee Trailhawk,
2005 Harley Davidson FLHTCUI

I dig all cars, old and new, whether they were hammered out of American iron, German steel, or Japanese tin cans. Being unable to appreciate them all is missing out on a world of great things.
But thats just MY opinion! :P