Removable links dont have to be on the top and bottom specifically, they just need to be accessible in any drivable orientation.

Thus if you put the link on the side, and it can be accessed regardless of inversion - it should pass tech check.

The simple reason is you dont want a robot driving into you as you try to invert it. With non invertible robots its less an issue because they cant drive into you as you approach (but still you should try to make the link accessible to make it as safe as possible).