As ua told you that partner, just removing the inner cover and with that you discover the 10mm nuts and it will depend on whether the mirror is manual or electric.
I have touched cases in which the electric mirrors on occasion the connector is well below the inner cover and if it is your case you will have to remove the panel.
Luck
Thank you for your advice, but I had to remove the upholstery because the mirror is electric.
It has been phenomenal.
Thank you