Cheap source for Yacht transport 300 miles in Tx.

On road on the water or what? There is no such thing as cheap transportation. If you pay peanuts, you get monkeys and in the end with a lot of damage that costs thousands more than paying a reputable source.

Betting between Lake Texoma and the coast....let's see if I guessed right.

If it has an arch, probably going to have to remove it. I think the bridge will probably clear otherwise, but not sure. If not, then will need to remove it.

Height is going to be the issue. You need to see what your height is and what it takes to lower it.

Post your move on Uship, You will get bids to move your boat and the website is free to post.

The specific standards for vertical clearance adopted for the Interstate System maintain its integrity for national defense purposes. On Interstates, the clear height of structures shall not be less than 16 feet (4.9 meters) over the entire roadway width, including the useable width of shoulder. In urban areas, the 16-foot (4.9-meter) clearance shall apply to at least a single routing. On other urban Interstate routes, the clear height shall not be less than 14 feet (4.3 meters). A design exception is required if this standard is not met. Exceptions on the Interstate must also be coordinated with the Military Surface Deployment and Distribution Command Transportation Engineering Agency of the Department of Defense.

Having said that, arterial, access and local roads may have lower structural clearances not to mention power lines and pole trusses. Reputable haulers will do the homework for you.

As for taking the boat apart, there's a lot to it, even just lowering the arch. I don't know your area at all but I'm going to assume there is no way at all from point A to point B on her own bottom. If there is, I would take it, even if it's several days journey.