Making an overlay stick to text

I downloaded a great distressed overlay and love the way it looks over my text.  My only problem is that I don't know how to make it fit in or stick to the letters - it's just a box over top of my text.

It looks great until I put it over a shirt for a sample ... The distressed layer is separate and makes my shirt look distressed as well:

Anyone know how I can make this overlay lay over top of the text and images ONLY?