Sorry for the delay…
If you:
1)create your clones with a cloner using the grid array
2) put a rectangular spline around your map spline (bigger than map)
3)add the 2 splines to the spline mask and set it to B subtract A(assuming map on top, then rectangle below)
4)add the spline mask to an extrude
5)add the extrude and the cloner to a boole
6)make sure the cloner is on top, then the extrude and that the boole is set to A subtract B

Let me know if that works for you…
Tim