C-Beam and Standard V-slots do not have the same rail opening. I have searched for C-beam did not find anything matching my needs. Those are low profile rail cover that will not take a lot of space in the rail, allowing you to conceal as much wires as you can.
Those have been printed with my prusa MK2s, just add as much as you need and scale the length axis according to your need/printer bed.
0.15mm, 100mms linear advance
no brim, no support, no raft, 90% infill
Sliced in Slic3r PE