[Jeff, Daniel]

We added a 6" to 2.75" Zero Length Reducer Flange to a Laser Filter Cavity (LFC) 6" Gate Valve. I tightened the bolts to 34 Nm until the copper flange wasn't visible. I placed on the optics table a t-slot framing (80/20) structure with some viton to support the ion pump. We then placed the ion pump on the reducer flange and I tightened the bolts until the copper flange wasn't visible. 

The cable to the ion pump fits, but it might constrain the composite 2.75" CF Angle Valve (that would go to the leak checker) from opening fully.