Retrofitting reading lights: Do you need to remove the headliner on an Audi A3 (8P)?

Hello,

I want to install interior lighting with reading lights in the rear of my A3 (8P) (currently it only has the standard lighting). However, I think two wires are missing from the connector that goes there. Does anyone know which wires they are and how I can get them connected? Do I need to remove the headliner? And what about the airbags in the headliner?

Best regards,