Hey Daniel,
I did a write up awhile back about the Bear Weather Rests. Like Pete said, the first thing I do is to remove the adhesive backing that comes with the rest, simply because it's too thick. Once removed I trim the bottom of the rest and the arm up to the B in Bear. I also take either a light dremmel or a buffing wheel and remove the hump in the middle of the rest, this removal brings my arrow closer to center. I like to use a think piece of felt where my arrow meets the riser side plate. This just helps with wear over time.
I than re-apply an adhesive my buddy Allen told me about. It's call "Peal n Stick" and you can pick it up at Michael's art supply store.
As you can see I cover the shelf in Velcro and than mount the rest right on top of the Velcro keeping it fairly close to my hand.