All in all, there are 90 degrees horizontally, and 180 degrees veritcally through which the flat mirror can be rotated. It should be mounted 90 degrees Vertically and 45 degrees Horizontally. The travel along the Ocular's Axis of Symmetry should be a good portion of the telescope tube's diameter.
The Objective Mirror comes next. It is positioned at the bottom of the telescope's tube. It can be Tilted out of alignment and thus has adjustment screws to tilt it back into alignment.

Left and Right in the diagram are defined by an observer standing beside the telescope facing the same direction in which the the telescope is pointing.