1x M3x6 Screw (A longer screw would allow support for more pen diameters)
1x M3x4x4.2 Brass threaded nut insert
Installation
Print the above parts.
Looking from the right towards the printer head, you will see 2 exposed screw holes and 1 slightly exposed screw hole. Use the cutters that come with the printer to reveal the third hole.
Attach the risers and screw in the mount.
Use a soldering iron to press the brass threaded nut insert into the hole on the pen holder.
Insert a pen, tighten the screw, and slide it onto the printer.