As stated in a previous post, my Dec 66 SJ 2+2 with interior decor option did have the deadener on the gas tank. However, the tank itself was only about 80% covered due to aging brittle material. I saw no evidence of deadener on the vertical risers around the tank nor on the flat sections to the left and right of the tank as Jeff's 69 & 70 documents show. I suppose that if they were there I would have seen either some pieces left or some loose remnants floating around. My vote thus far, and this is a very interesting topic, is that 67-68, models with interior decor (aka deluxe interior) had sound deadener material over the trunk. Of course we would need more samples, from more plants, etc. to make a better case. I don't have access to the Osborne manuals yet, it would be interesting if they called any of this out. If this speculation gains more merit it would be interesting to probe into differences in the interior deadener application. John