Yes, I pulled the single mode diodes and tryed to replace them with P73 diodes. I screwed up and put in 3, LPC open can diodes instead. Boy, are these dim in comparison. Fixed this and mounted these on the stainless bar. Aligned and focused I measured the centerline for each, 635.8, 635.8 and 636.1 nm. The band width down to about 30% of peak (not the standard 50%) was 1.7 nm for all of them. Everything else ready for the moment of truth and here I am stuck at a resort in St. Lucia. It's brutal. So, a few days to get past this and back to work.