Maybe too late to help, but this was a recent post so I'll chime in. I just got those exact upper door skins to replace my OEM skins (from Amazon too). Like you, I thought they were too small at first. But I just kept pulling and tugging and massaging, and eventually it stretched out enough to fit on there. It was a lot tougher than I expected, but it turned out nice and tight. I'd rather spend an hour getting sore hands and have a tight door skin than have a loose skin for years to come. Mine looks much nicer and tighter than the one in the picture on Amazon.
Oh, and the second link to Qtec is for YJ upper door frames, not TJ, in case anyone is looking for TJ frames.