It would not be worthwhile going to all that trouble just to engrave the character '8' on one occasion.
Assuming you really have a more extensive requirement the simplest thing might be to use a GRBL shield to control the motors and the GRBL program which responds to GCode instructions.
Of course as you have not tole us what stepper motors you are using I don't know if the stepper drivers that go with a GRBL shield would be suitable.
...R