Kyle R., Rakesh K. 

After having everything go wrong that could go wrong, it looks like we might now be free of this burden.  The main difficulty seems to be that our custom nipple had two fabrication issues.  The first being that one of the two pieces comprising the rotatable flange was out-of-round.  The other being that the knife edge at the rotatable flange end was too recessed from the plane of the flange.  Thus, I could nearly achieve a metal-to-metal (flange-to-flange) connection without the use of wrenches!  WTF.  Using only my fingers, I could bring the mating flanges together with only the final 0.010" requiring the use of wrenches!  

As such, I was quite surprised to find that this joint, as well as the other new joints on the pump side of the new 10" valve, passed the initial He leak test.  Rakesh and I will follow up Monday with a more "scrutinizing" look but nothing to indicate a problem. 

Also, the Turbo spun up smoothly with no "viby' RPM zones during acceleration.  I had changed the isolation/mounting for the rigid valve connection and, as a bonus, seems to have improved this unit resonances.  

I am leaving the Turbo spun down, levitated and under vacuum over the weekend.