See attached photos for the internal layout of Zach's cantilever cryostat (all internal components left in cryo lab (except the heater)) The holes are on a 1cm grid and, I believe, are threaded for 4-40 (will check Monday). The internal 'window' is about an inch off the colplate. There is ~2 inches of space from the colplate to the first radiation shield lid. 

The external optical port on the vacuum tank is 1.75" from the bench and is 0.75" in diameter. The cryostat is missing the lid o-ring, electrical feedthrough vacuum port, and intermediary valve between the vacuum space and the vacuum pumps. I will search for these on Monday.