E61 Hydraulic liftgate ball issue
 

I have a problem with the hydraulic lifgate ball. When trying to replace it the other day, seems the welded nut inside the frame let go. So now I have to cut some metalto be ableto get a wrench in there since there are no openings. As anyone had to do this? any pics or advice?

Have you checked to see if you have any access from inside the car if you remove the D pillar trim? That may be complicated with the cargo cover mechanism.