Can this be rewitten to control axis locally instead of globally?

Here is the Code:

 rigidbody.rotation = Quaternion.Euler(rigidbody.velocity.z * tilt2, rigidbody.rotation.eulerAngles.y, rigidbody.velocity.x * tilt);

This code currently is controlling tilt/bank of my player controller through its rigidbody. It works great but only on global axis. Is there a way to write this code out so it gives me same control but on the local axis?

I've tried this:

 rigidbody.rotation = Quaternion.Euler(transform.TransformDirection (rigidbody.velocity.z * tilt2, rigidbody.rotation.eulerAngles.y, rigidbody.velocity.x * tilt));

... No dice!

Entire code looks like:

 using UnityEngine;
 using System.Collections;
 
 [System.Serializable]
 public class Boundary
 {
     public float xMin, xMax, zMin, zMax;    
 }
 
 public class PlayerController : MonoBehaviour 
 {
     // Places specific attributes in Player Inspector
     public float speed;
     public float tilt;
     public float tilt2;
     public float RotateSpeed = 30f;
     public Boundary boundary;
     
     
     void FixedUpdate ()
     {
         // Boat X and Z axis movement
         float moveHorizontal = Input.GetAxis ("Horizontal");
         float moveVertical = Input.GetAxis ("Vertical");
                 
         Vector3 movement = new Vector3(-moveVertical, 0.0f, moveHorizontal);
         movement = transform.TransformDirection(movement);
         rigidbody.velocity = movement * speed;
 //        rigidbody.velocity.x(moveHorizontal * speed);
 //        rigidbody.velocity.z(moveVertical * speed);
         
                 
         // Restrains Boat movement
         rigidbody.position = new Vector3 
             (
                 Mathf.Clamp (rigidbody.position.x, boundary.xMin, boundary.xMax), 
                 0.0f, 
                 Mathf.Clamp (rigidbody.position.z, boundary.zMin, boundary.zMax)
                 );
         
         // Boat Tilt and Bank
         rigidbody.rotation = Quaternion.Euler(rigidbody.velocity.z * tilt2, rigidbody.rotation.eulerAngles.y, rigidbody.velocity.x * tilt);
 //        rigidbody.rotation = Quaternion.Euler(transform.TransformDirection (rigidbody.velocity.z * tilt2, rigidbody.rotation.eulerAngles.y, rigidbody.velocity.x * tilt));
                 
         
          //Boat Y axis Turn/Rotation        
         if (Input.GetKey(KeyCode.Z))
           transform.Rotate(-Vector3.up * RotateSpeed * Time.deltaTime);
         else if (Input.GetKey(KeyCode.C))
           transform.Rotate(Vector3.up * RotateSpeed * Time.deltaTime);
     }
 }