Moving Center/Pivot point with blender models

I have actually created a script for this a while ago. Put this in your Editor folder and it will be under the Custom tab.

 using UnityEngine;
 using UnityEditor;
 using System.Collections;
 
 public class ChangePivot : ScriptableWizard {
     
     public float offset_x = 0;
     public float offset_y = 0;
     public float offset_z = 0;
     
     public bool shared_mesh = false;
     
     public GameObject obj;
     
     [MenuItem ("Custom/Move Pivot Point")]
     static void CreateWindow()
     {
         ScriptableWizard.DisplayWizard("Move Pivot Point of Object",typeof(ChangePivot),"Move Pivot");
     }
     
     void OnWizardUpdate()
     {
         
     }
     
     void OnWizardCreate()
     {
         change ();
     }
     
     void change()
     {
         Mesh mesh;
         if(!shared_mesh)
         {
             mesh = obj.GetComponent<MeshFilter>().mesh;
         }
         else
         {
             mesh = obj.GetComponent<MeshFilter>().sharedMesh;
         }
         Vector3[] temp = mesh.vertices;
         for(int i = 0; i < temp.Length; i++)            //Loop through and move the object's mesh
         {
             temp[i] = new Vector3(temp[i].x + offset_x, temp[i].y + offset_y, temp[i].z + offset_z);
         }
         mesh.vertices = temp;
         
         obj.GetComponent<MeshFilter>().mesh = mesh;        //Just gotta make sure we make get the mesh back to the object.
     }
     
 }