TS-850S Frequency calibration

The frequency display of my Kenwood TS-850 seemed to show a little bit too low frequencies, so I decided to calibrate it. Of course I made a search in Google: TS-850 frequency calibration. I found this link.

OK, good instructions...but how to do it in practice? The rig is new to me and I don't know how to open it in the first place! A search in Youtube provided me with...yes, really hands-on instructions:

Now my rig is calibrated. In total it was a 10 minute project, including the instruction searching and screwdriving.