thanks kevin. windows already instaled. what would be a good way to attach the sills?
Stool or sill, you still have the same issues, mainly that the fence on the domino requires about three inches of clearance to register.
For sills, I build a window unit (I.e sill, header, and legs ) sometimes using sipo dominoes, and pre finish. To install I counterbore woods crews in the sill and use 15ga nails for the head and legs. For a stain grade window unit I plug the screws or use pocket screws. Make sure you slope the sill at 15 degrees on the top and rip a drip edge into the bottom.