The black part of the pad is a 2 piece thing and the slide thumb pad is in it. I took it apart,removed the red slide pad,widened the hole a tad more,dremeled the nub on the bottom of the pc-engine thumb pad so it would be flat,and with a dab of superglue for bonding placed it on the circle part,the part you see in the pic. On the backing to make sure it never came loose causing the thumb pad to get out of alignment,I added a tad more wood glue,a small layer that is enough to make sure it all stays in place. Then while the glue was hot snapped the 2 black pieces together.