I do all kind of tips. Dont worry about the boo. IF you sad it flat, what ever you put on the tips will hold it down. IF you go down to the ipe, Id suggest you do it in a angle. Taper it, if you will. That way you will have some of the boo under you tip material to help hold it down.

This one is in an angle. I sanded through the boo and ipe. I put a thin layer of ipe down first, then mesquite, then antler.



Here is a side view. Kind of bad pic, but you can see what I mean by holding the boo down. This bow has a layer of ipe, on top of the boo, then osage, and then antler. You can see what I mean about sanding it in an angle. Either way you do it, just have some/all of the boo under your tip overlays.