Eventually, I got it turned right and tight so I went upstairs to see how this all lined up. In this first picture, it looks really good! You can see right down into the pipe!
Unfortunately, the angle of that shot isn't perpendicular to the floor. Here I've put the camera against the wall shooting straight downward and you can see the hole and the pipe don't line up. This was my greatest fear, that my pipe wouldn't be long enough.
And downstairs, this angle looks good.
But this angle doesn't.