MakerSlide/(T-slot 20mm) Pulley Bracket

My original printer was made from components salvaged from a 1980's xray copier. Great stuff but way too much mass for quick printing. So I am building up a H bot with MakerSlide. This will have a lot less moving mass.
The H bot requires six pulleys to guide the belt around the figure H. I created a simple bracket that fits in the 20mm t slot. I designed in a nut holder but I put it at the wrong orientation so it won'f fit in the slot as is. Rather than reprint, I just put a 6-32 screw and nu