Pen holder for this extruder, https://www.thingiverse.com/thing:1926655 simply add with existing mounting holes, and easily remove when not needed, without having to disassemble the hotends.
By using a well fitting dovetail slot with two small rubber bands to allow pen to follow any surface while keep a light downwards pressure.
One pen mount to be used with a 0.3 Ultra fin sharpie
A second mount to be used with a Fine Point sharpie
If you use a other popular brand of pen with different dimensions I could make a holder for it.
I included helper files for those who uses S3D, to print drawings or PCB'S, if you want the print to start at a corner as a x0 y0 start point so you can setup a alignment jig REMEBER it can be anywhere on your print bed, in the middle or anywhere else, as long as the Axis has the room to move to according to what you are printing.
Also important to place your prints alone the X zero axis and along the Y zero Axis. See alignment example jpg
Here is a GitHub link to a very easy and very good image to stl converter.