Finding a gameobject in native code

Hi,

I am trying to use C++ code to call C# code and am struggling to find any definitive guide regarding how to find a preexisting game object/script? I would presume I need to find the gameobject to then find the attached script component. I have so far managed to implement the functionality required but with static calls but would rather find a single instance of the script to then call myself. ?I presume UnitySendMessage would perform similar functionality. Can anyone give me guidance how to do this?

Cheers,