How to rearange / set order of a custom editor in the inspector window ?

Questions & Answers
1

Is it possible to place a custom component above the transform inspector ?

2

Found it, but looks like it can be brought up just before the transform inspector. Once the target reaches the 2nd place the function returns false and it stops lifting it up.

public static void MoveToTheTop( MonoBehaviour target )
{
    // MonoBehaviour -> Behaviour -> Component
    if( ComponentUtility.MoveComponentUp( ( Component ) target ) ) 
        MoveToTheTop( target );
}

Had a look at the following:

  • Editor/Mono/Inspector/InspectorWindow.cs
  • Editor/Mono/Inspector/Editor.cs
  • Editor/Mono/EditorWindow.cs
  • Editor/Mono/Inspector/EditorDragging.cs
  • Editor/Mono/ComponentUtility.bindings.cs
  • Editor/Mono/ComponentUtility.cs

source : GitHub - Unity-Technologies/UnityCsReference: Unity C# reference source code.