Since Rob appears to have abandoned this thread, the link provided by Stan has proved very helpful. There is much more information here, than the first link. Even assuming the girl in the chair is at full recline, it looks like you could comfortably view to 60 degrees above the horizon without much neck-bending at all. A little neck craning could possibly take you to the zenith without much discomfort. I think I may try modifying one of these chairs with a binocular mount.

I've considered this also, but now that I know about the Suntracker, I think I'll try that first.

You guys are a valuable resource! Thanks.