IAS (DCook, JOberling) setup for pitch & yaw alignment on the BS optic. IAS directed SEI to perform a CCW yaw of 400urad. JWarner did a 1/3+ turn of all HEPI Springs to go CCW. IAS then reported ~45urad CCW remained. SUS TSadecki continued to do Pitch adjustments and the Yaw number may change slightly. This CCW Yaw calculates to move the BS ~0.1mm -Y. Based on the alignment results of 28 March the BS was already 0.8mm -Y and it looks like we pulled it East (-Y) close to 0.1mm based on the Dial Indicators.  So, Jim did a very careful +Y translation (west) of ~1mm with the HEPI Springs.  Jim did two rounds of 1/4turn west of all Springs.Based on the Dial Indicators, this is what we ended up doing.

From the last time we did an Optical Table elevation/level check we have shifted up 0.1mm with only 0.03mm tilt over the span of the Optical Table.

From the X Y Z alignment (28 March) we shifted west 38mils & north 4mils.  The rotation imparted by the translation since Yawing the table this morning is 0.0urads.  Yes 0.0; the DIs all read the same translations implying no rotation measured--Good work Jim!