Hi Cubanace ))))
Great progress, keep it up.
Regarding the internal mirrors, I am certain that the PAK FA only has two large mirrors , one on either side of the cockpit frame fixed to the sliding section of the cockpit. If you look at pics of the first prototype the cockpit frame has a central section running above the pilots head, so I guess nothing was to be gained with a third mirror. The later prototypes had the sliding section of the cockpit as frameless without the central rail.
If anyone knows different it would be good to clarify.