If its a three piece bow you can simply grind a thin wedge and put under the limb and change tiller that way without harming the bow .
You can try different thicknesses of shims in the bow first and then make the final product to the thickness of the shim down to zero in the back./ , You can then drill the holes and even glue it on the limb if you would rather have it there instead of the riser. I would use just a dab of glue though so you can take it off if you decide you don't like it.
God bless, Steve