This is mounted to the camera body with three screws. The camera body is mounted to the mount with 4 screws.
Rotations are possible at each stage.
No adjustment is possible. However, the whole mess is such that there is a pretty good alignment between the E-W RA tracking and the CCD pixels. When I turn off the RA drive and take an exposure, the stars track pretty well down the CCD column. I have not tried to measure this, but when the RA drive fails, one gets star streaks down a column. I have not noticed that they are diagonal.