Jeff,
Those photos help immensely!
One thing of possible interest - I was told by Scott over at the CJ registry that the rear edge of the rubber is supposed to slide over the rear edge of the radiator support, which your first photo clearly shows. As well, when clips are used, in order for them to work the seal must be attached in this manner. However, over the weekend I looked through all the photos I could find online of stapled seals on original '68 and '69 cars and noticed that several that clearly showed the rear edge sticking up at an angle, not slid over the rear edge of the radiator support at all. It seemed as if the seal was simply laid down flat, seam between rolled-under rear edge and flat area aligned with rear edge of radiator support and then stapled. Have you noticed this? Do your photos from '68/'69 cars support or contradict this observation?
One more thing ... if I could actually get a hold of a set of clips I would just as soon avoid drilling the holes for staples. As you say, it could go either way in '70. Does anyone know a source for the clips?