I have a bow with maple and walnut in the riser. The finish is, I'm almost sure, sprayed lacquer. The maple, having very small pores, is well finished. The walnut, with its much larger pores does not appear to be filled. Can I sand in a Tru Oil finish over the lacquer? I've done quite a few gun stocks and got a nice semi matt or egg shell finish with Tru Oil, but don't know if it will stick on the lacquer.