You need to remove the side vent, it is screwed on top and bottom (1 nut and bolt up and down) to an angled metal bracket welded to the fender inner surface.
Then you have access to the master cylinder, together with the removed access door in the wheel well it should be possible to remove the master cylinder.
It sounds like your car has no removable access door in the front wheel well.
In this case you need to loosen the wheel well by the screw clamps and bend it carefully away from the frame if access through the side vent is not enough for you, it is flexible.