Very Nice Doug. I've actually been contemplating something like your push off/pull on frame, as i'd like the option to be able to automate the roof opening (which I cant easily do with my flip open roof).
My setup also means that the underside of the roof is open to the sky when the roof is open, which means it collects dew, which I need to deal with before I close the roof again - whereas your setup would likely prevent that.
hmm - ideas to think about