The link is basically for a 45 degree diagonal, which I happened to have one lying around. I bought it a couple of years ago to try something with the Newt, but I didn't have enough "in focus".
I just put it in the scope and swung it around to a pipe on the neighbours roof, and low and behold it was right side up and right way around. There must be a difference in the light path for a 45 compared to a 90 which results in the correct view. The quality isn't the same as my 90, but hey I only paid $60 and I will only use it rarely...like on the neighbours
