I did mine back in September (title, register, and license). Think all total it was about $180, but I did the personal truck license at 18k GVWR, so we can still use it when we want to.
As Ty said, the title fee is minimal, and the antique tag is $27.75 once, and forever.
Here's a snippet from the TN.GOV website's Antique Vehicle application:
ANTIQUE MOTOR VEHICLE LAW
Antique Motor Vehicles. Per Tennessee Code Ann. § 55-4-111, a person may register a vehicle as an “antique motor vehicle” providing that certain requirements are satisfied. The vehicle:
• Must be a motor vehicle over twenty-five (25) years old and have a non-modified engine and body,
• Can be used for participation in, or transportation to and from, club activities, exhibits, tours,
parades, and similar uses as a collector’s item,
• Can only be used for general transportation on Saturday and Sunday, and
• Can be used on any day for the purpose of selling, vehicle testing, or obtaining repairs to or doing maintenance on the vehicle.
Note: Both cars and motorcycles may be considered antique motor vehicles, if all provisions are met as stated above.
No renewal required. This registration is a permanent registration and is not required to be renewed annually. Once assigned, the license plate cannot be reassigned to another vehicle.
Good Luck!