For a resolution of 1920х1080, one grid cell is 11х11 pixels.
I open a pre-saved grid, then screenshot the views in x2 mode (that's only two screenshots per surface), and save them on different layers. Then I stitch each surface together. The grid is on a separate layer, so it can be easily toggled on/off. Similarly, potential Dragon Utopia areas and calculated routes between cities are kept on different layers.
This is what it looks like

I'm attaching my grid for the 1920x1080 game. In principle, if you stretch it correctly, it should work for all cases