A game I'm attending asked me to swap out the black parts of the BK1S, so I've designed this file that replaces the pinned top rail with a 3D printed section that can be whatever color you desire.
Print settings
The whole thing prints without supports, just be sure you have your printer set up to bridge the gap on the bottom in the slicer. I unchecked slow for overhangs and turned bridging speed up to 100, though ymmv