2+2+3 More Plasma builds, double the joy ! 3X2M and 2.5X1.5M cnc plasma build.

Can you please point me in the right direction ?

I would appreciate that very much!.

Here is "my" schematics:

That is exactly where the THCAD should be connected, the red on the left side of the schematics.
What THC are you using ?
THCAD 300 can be wired at those two points although in the manual it explicitly says not to use it with HV start plasma, but i am using it with HF/HV plasma with no issues at all, wired at the same spots as you have marked on the left with red.
For THCAD 10 you would add a 1MOhm resistor to EACH of the wires, so two resistors in total.

Im planning to use the THCAD300 (hence I do not have eny voltage devider and did not want to fiddle with that part)

And if it cooks, then I might have to try the THCAD10V and make a voltage devider as you describe, with the 1MOhm resistors at both leads.

Thank you weary much for the input, I can now move forward in my projekt

Is there a reason why you used the 300v and not the 5v or 10v with additional voltage devider for the cebora?

It is just easier for me to use the 300.