Here's a piece of code that generates a grid of metrics. You have to define your coordinates in a metric projection such as UTM.
You can generate 2 grids at K and K/5 spacing and work out the naming by cross section and use the col and row attributes in the map.
coveringGrid(proj, scale)
Returns a collection of features that cover this geometry, where each feature is a rectangle in the grid defined by the given projection.
Arguments:
this:geometry (Geometry):
The result is the grid cells that intersect with this region.
proj (Projection):
The projection in which to construct the grid. A feature is generated for each grid cell that intersects 'geometry', where cell corners are at integer-valued positions in the projection. If the projection is scaled in meters, the points will be on a grid of that size at the point of true scale.
scale (Float, default: null):
Overrides the scale of the projection, if provided. May be required if the projection isn't already scaled.