i started assembling today (no glue yesterday....i faintly remember my son asking me for some wood glue a while back)and i used my utility knife to cut out the wedge and i took that little piece with it so now its on the wedge not the bar.
That is exactly how i do it. Use the box cutter to cut the wedge out and leave the excess piece on the wedge so that the top bar is smooth. If you just break the wedge out, it tends to leave some on each piece. Now you can just flip the wedge over when installing so that the excess faces down. Or what I usually do is take my thumbs and just break it off. No need to spend anytime sanding.