This one's for those using Grease Pencil (or for any other use you can imagine). The script positions the first selected object behind the second object at a defined fixed distance, following the Y-axis. I needed this the other day.

*IF YOU NEED TO POSITION IT IN FRONT, JUST SWITCH THE NEGATIVE SIGN TO POSITIVE.

*IF YOU NEED TO USE THE X-AXIS, JUST REPLACE THE Y WITH X IN THE SCRIPT TEXT.

See it in action here:
https://www.instagram.com/p/C0HVnGRALor/

**If you have any suggestions for improvement, leave a message in the comments.