You want to loop over the values in grid, and use ax.text to add the label to the plot.
Fortunately, for 2D arrays, numpy has ndenumerate, which makes this quite simple:
for (j,i),label in np.ndenumerate(grid):
ax1.text(i,j,label,ha="center",va="center")
ax2.text(i,j,label,ha="center",va="center")
