You definitely should replace the ball joints then, they may feel nice and tight but under a load they may act differently and once you get foreign materials in the grease, they could bring about disastrous results. Theyre very inexpensive compared to the alternative. As far as adjusting the sheet metal, it may not be feasible if its all in line with the body, without making it all mis-aligned. If all of the door-to-fender and fender-to-hood joints are inline and spaced corectly, then it could be that the subframe being a lil crooked is whats causing the problem.