You can modify grids and graticules using the options outlined in the help topic and even make one which you can save for future work
covers the options, and there is even a tutorial in the help topic table of contents in the link
Thanks Dan. Have you been able to create one like in the picture by modifying the different components? My goal is to make it close to what it looks like on a sea chart with a ruler/scale bar-like frame.
It looks like you want to vertically offset parts of the graticule label with the degree above the decimal value. Currently there is no solution for this. You will need to convert the grid to graphics and manually adjust and move the label components.
Feel free to add this to the ideas site for future consideration.
I'm not familiar with "graticule rulers". This is not something we support "out-of-the-box" in ArcGIS Pro. As this seems to be specialized functionality I would recommend posting your question on the specialized community sites like:
You might find more useful information there.
Hope this helps,