We're missing some key information: the width, placement, and count of the window wells. We currently only know that there seems to be more than one and that they are 3' deep from the house along a 12x50 strip.
But as an idea with what information we've got, what about using triangular head placement, with heads placed at the center-edge of each window well spraying away from the house with a 210 degree arch (i.e. partially spraying back towards the house, but not at the windows) with opposing heads located at the far edge of the strip between window wells spraying toward the house.
Here's a
ROUGH sketch of the concept.