Larry’s description is the common approach to many manufacturer’s TD kits. I have seen none where the “flat bar” actually bends around the corners of the windshield frame slot.
Classic Roadsters tops had small tabs the fit into the slot on the two sides. But they are separate pieces from the main bar. AAnd they were sewn into the fabric of the roof.
Most of the other manufacturers simply wrap the corners of the roof around the frame and use snaps on the inside portion of the frame.
The gas through the radiator cap is the standard Classic Roadsters approach, since they provided a new gas tank, which sits on the floor. Many of the other manufacturers reuse the VW tank, so the “through the radiator cap” design is not feasible.
Post a few pictures and we may be able to help identify the manufacturer.
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica Roadster
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