Hi guys.. I got a problem on my hands. Everything is going well... EXCEPT the darned nut thats attached to the upper ball joint. This is a 126 300SEL. The nut just keeps spinning. Its moving... because I see it move, and the nut is not stripped, however I spent a good 10 minutes turning the nut but its not coming off. I don't think it even moved much. What should I do??? I need this fixed ASAP since this is my only car. Help on this matter is greatly appreciated....

P.S. This is my first ever "project". I wonder if replacing the lower ball joint is too advanced for a beginner DIY, but I am up for the task