I think I sorted it out. I was more careful keeping the passenger side straight. So assuming those were correctly aligned to begin with and based on the wear patterns on the pads, it appear the heat shields should be aligned as in the attached picture if you're looking at them from the front of the calipers. The open slot starts at the middle of the rear and run around the top to just below center on the front. The pistons are aligned with the slots. Brakes work great with the calipers rebuilt, new lines and flush!