A major milestone was achieved last Friday--I rolled the roof off the observatory! Conditions seemed optimal; the morning was very still with no wind, so I figured it was a low-risk as it was ever likely to be to roll the roof off by myself. I rolled it very slowly--it took about a minute to roll it off completely. It was very easy to move and required little effort. I'm delighted by the result. This week, I will begin cutting holes for the scope tripod.