Looking for Schlumberger Enertec 5224 oscilloscope manual and schematics

[jloupdef]

Hi,
I bought a non working Schlumberger Enertec 5224 oscilloscope, hoping to repair it.
I am going to open it for cleaning and inspecting if anything is visually broken.

I am seeking for service manual and/or schematics.

Already have the user manual which can be found online (47 pages in french), but it is not enough for serious repair.
Anyone with anything would be an amazing help !

PS: I know i need be cautious when opening it because of high voltage.

Thank you all !