Backer for the 3-Wheeled alternative to the H-Bar bracket. I reduced the width a little bit for slightly more Y movement.
Using 4 wheels to ride on the rails is over constraining, this also allows you to easily adjust the tension with an m3 bolt and nut.
Finally printed these. Updated m3 nut hole size to standard thickness.
Print with a decent number of outer layers to increase rigidity and strength