I can't visualize what you're talking about...maybe its a PO thing? (ie: useless) I can say that the factory dual exhaust lines have a special line setup (another flexline toward the back of the car IIRC) to help with clearance that is preeetty expensive. A lot of people have modified single exhaust lines to clear, and that's what I'd do if my car hadn't come with a new set of GT lines (but no flexline :wall

A new set of lines is a good idea after 40 years anyway. My old ones looked good, but split into 3 pieces when I laid them on the ground.
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66 coupe 5.0/T5, home-brewed power 4 wheel disc setup, 350hp+, looks like it belongs in 1968