If it helps at all, there appears to be 2 very common versions of the header seal. The good version is like OEM in that the U channel that goes over the pinch weld at the rear of the frame is molded at 90 degrees to the rest of the rubber. The terrible versions are molded flat and they roll them up to ship them. The OEM style have to ship straight or mostly straight in a long skinny box. The other problem with the rolled up version is the U is too tight at the bend of the U. When you tap it on the pinch weld, it spreads the lower end open too far, doesn't look good and then won't stay on very well.
I've ordered and returned 4 of them trying to get another good one that works well. A couple from the same seller who sent the good one, I ordered another one because the first one was nice, got the crap one instead. Back it went.