How do you get under the fender. do you have to take it off or can you get to it from inside the engine compartment somehow. just wondering, mine is kinda loose and i want to tighten it.

 

You have to remove the fender to her to it, however you shouldn't have to get to it to just tighten it up.
One side has a notch in it so it will not twist when you tighten it, just get it seated in that position by pulling antenna up and use a wrench to tighten the collet

 

If you remove the inner fender well, you should be able to get to it. IE: the plastic that keeps crap from your tires from getting all over your door hinges. It's secured using the same screws that hold the flairs on, and some plastic snaps.