W124 rusty wings

[JWC1982]

Hi,
I have a w124 and currently it has a rest hole the size of my fist in the wing (my fist didn't make the hole either!). Can anyone detail to me the removal of the wing and what's involved? Can I do this with scanners and sockets or will grinders and welders be required to repair/replace?

 

[312 Sprinter]

It's a bolt on, there are screws hidden inder the plastic trim over the sill/wing joint, an awkward one on the door shut, along the top of the wing and hidden by the indicator