gearbox oil change on a 2 valve Norge

Hi. I wonder if anyone can help and save me time deconstructing unnecessary parts of my Norge fairing to get to the gearbox filler and drain plugs… The owner’s manual says take it to your nearest dealer and my workshop manual just shows the exposed gearbox. Not had it long so it’s the first time I’ve done this. Next job is the air filter for which I need to remove the petrol tank but at least the workshop manual covers getting the tank off.
Many Thanks in anticipation. Duncan.