The polarization into HAM 2 is changed inside the PSL table using an additional wave plate. 
After aligning the IMC yesterday back to flashes, today we checked the beam on the periscope mirrors in the PSL and on IMC2. It is reasonably well centered on the periscope mirrors (within 2-3mm) and as far as we can tell within 2mm centered on IMC2 in Yaw and within 1mm in Pitch. 

We removed the wave plate after the IMC from its Siskiyou mount and bolted it on the table next to the mount. This turns the polarization back to the polarization we want in the Faraday and the beam clears the Faraday w/o a problem. 

One issue: IM3 is misaligned by a lot in yaw and some on pitch, barely clearing the elliptical baffle. This is consistent with the changes we saw in OSEM readings of 18mrad in yaw and 4 mrad in pitch between December and now. It is not clear where this is coming from. 
Other mirrors on HAM2 don't show these large changes but we also had to tweak IMC1 and 3 by a few mrad to close the beam path. 
Something to keep an eye on. 

We left the polarization in this state; Chris and Rodica will continue alignment and power measurements next week in this stage.

Joe Gleason, Deepak Kumar, GM