Looking for Metrix MX53 Multimeter schematic

Hi there,
After many years of good services, I made a mistake while measuring UHV (ultra high voltagel with my  METRIX MX53) . I was measuring a voltage around 2500V DC with all the safety required, using a divider, to get only 1/50th of the voltage as I did many times.
But for some unknown reasons (I'm rarely distracted when playing with such letal voltage) , I didn't connect my clip at the divider but at the full voltage. 
You understand that the MX53 didn't appreciate it. 
I opened the multimeter, which is kind of sport as not as easy as it looks and found a resistor R1 (may be 200 ohms 5%, hard to read) completely exploded. I replaced it. I also found that 2 of the four varistors were shorted, changed them, I checked all the transistors, mostly SMD, but they all look fine as far as I can see. However, the multimeter is still not responding. 
I have also found 2 SMD diodes that could also be shorted and need to check them more thoroughly... 
I have very few chances to fix the meter but if I could put my hand on its schematic, It would be easier to track down the culprit, hoping it's not the proprietary chip in it. 
So, if someone have (or could lead me to a link to it) the circuit drawing of the MX53, preferably, or the MX52 or MX54 which look close to it, just a few functions more and the PCB looks common to both as the MX53 has some locations not populated with components, it would help me to try to save my old companion! 
Thanks in advance, any help much appreciated.!
Nota: METRIX is a French company, was also know as Chauvin-Arnoux.
Regards from France...!