Menu: Scroll to select non-CPU lens data, choose a lens number (1 through 9), Enter the focal length and aperture (longest if a manual zoom, and widest f2.8 etc.) select done.
Now, I have stumbled across a few older lenses and snapped them up for Video use which required alteration, I use Steve's Camera Repair in Culver City for anything old school. They will do mods for cine-functions as well.
Also some AF primes like my 85mm f1.8 require the iris to be set to the smallest aperture in order for the camera controls to see it, but the indent stops are adjustable with the normal wheel on camera. Moving the iris will cause ff or error, lens cannot be found.
That's it, and set the camera to manual focus of course. The little
"in focus" dot will illuminate in the viewfinder, when the lens is dead nuts, on most lenses.