You can go-cart a FFR, Hurricane and others that have a body shell that fits over the frame. Unique, Lone Star, Everrett-Morrison and others, you can not go-cart. It's the way the body is build. If the interior tub is molded to the outer body you have to build the car with the body on the frame. It's not easy to take the body off after you have completed the build. Windshield, lights, dash, hood, doors, trunk, etc would have to be removed.
Maybe I can post some pics that will help.
Dwight
Hurricane go-cart
Hurricane body
body installed