These are the photos: https://ibb.co/qrvpX7c
https://ibb.co/44L8CFH
If we see the cables from the right, they are the ones that are after the two free holes in the first image, in the second they are the connected ones where it says courtesy light.
An external switch should be placed on these same contacts. When it is on or with its contacts closed the light will turn on until you turn it off. What if, be careful to turn it off from this switch since otherwise it will never turn off for more function than the gate. regards