The factory flanged flange containing the inadequate fasteners was "gappy" enough that I tried the easy in-situ replacement of its fasteners but unfortunately it didn't work (2x10-8 torr*L/sec leak) and I had to vent the RGA volume and replace the gasket along with adding the good fasteners -> pumped down RGA volume and leak tested new joint -> No leak detected (Leak Detector baseline signal 3.5 x 10-9 torr*L/sec helium).  I didn't have the RGA laptop so I'll need to go out again at the next interferometer (IFO) downtime to verify the the RGA works after having being withdrawn from and reinserted into its protective nipple (this exercise can result in a grounding of some of the tight clearance electrodes upon re-insertion).  

Leaving work area shut down, i.e. there are no pumps running or related electronics energized etc.