I have an issue with the tub spout not being flush with the tile wall. I've attached a picture that shows the problem. The spout is a slip on with a hex nut for tightening. The copper pipe coming out of the wall is 2 7/8 inches so I don't think it needs to be shortened. I've tried a different spout, but still have the gap. Also tried using a collar and spout, but still have the gap. Can anyone offer a suggestion, aside from a whole lot of caulk?