This is one of those rare cases where a RAS would come in handy.
Start with a 2x2 workpiece, cut 45 degree notches placed at the fixed
interval and cut only slightly deeper than the diameter of your drill
hole. This step is REAAALLLY easy to do on a RAS.

Now you have flat platforms, pitched at 45 degree angle, to drill your
holes. Drill them deep enough to reach the depth of the final board.
After drilling all holes rip off the stepped edge to your final
dimension of 1 inch thick.

TWS