Loose front in Canon EF 24-70mm 1:2.8 L USM mark I __________Motion Lapse Film

This Canon EF 24-70mm 1:2.8L had been assembled wrong by another person, or been used very hard. There was missing screws inside and the bajonet also miss 1 screw. The problem with the loose front was that..., the same 3 screws that always come loose in the front section... It's not that hard to fix, just use a good JIS00 screwdriver (modified PH00...) and a sharp tweezer and one with rubber on the end. Just remember to set some small marks and take care of the flex cables, also when putting back the USM, be aware of the little tap for the focus, that connect to the most back focus lens.... There fall out a little piece of plastic, it miss the screw..., but it works fine without it, and because I only have the parts manual, I do not have the detailed info about this lens :-(