Surface appearances do not tile cleanly

Currently I am trying to make a world map image out of 64 parts, but the surface appearances don’t tile cleanly, shown below;

This is really annoying as I need the extra detail. The way I got around this in the past was by using an image with a SurfaceGui, as a decal had the same issue. Linked below is the original way I got around this in the past.

Sorry about this, but I need to bump this, I need help with this!