Originally Posted by Redneckstone
buy a new tail gate personally
that is completely unnecessary. It looks like its just surface rust. All you need to do is sand all the rust off, and sand the paint surrounding it until you get into solid paint that isn't comming off, and feather the edges. Then put a couple coats of primer on. Then sand it with 500 grit sand paper.
After that, spray the paint on the area....try to feather the paint out it out around the area so that it will blend better, instead of painting a little square over the area (it will be more noticeable b/c you can see right where the old paint meets the new paint).
Then spray a few coats of clear on, going just past the area you painted (make sure you scuff the paint where you plan to put new clear on). After it dries, you should be able to polish the area with a buffing compound, or rubbing compound so it blends. It really is not hard, specially since its a small area.
If the rust is too much to sand off, you can get some rust converter and brush over the rust only. It will convert the rust so you can paint over it. You can get some at your local paint store.