67 barracuda fastback original trunk carpet black

This is interesting, I thought I was the weird one. My '68 cuda FB originally came with a trunk matt made from the black truck floor matt material, but standard size. I saved a piece of it. It is just like the trucks- ruff, cobbly, black. I have not found anyone using this material. Another detail- since my car has the optional 5.5 wheels the spare tire sticks up higher in the wheel well. To compensate, the factory glued extra thick insulation material to either underside of the matt to compensate for the bigger "bump" in the middle. Is this just me? I have never seen another. I assumed I was looking at a one-off, where the factory just used what they had on hand at the time.