Tail follow object - getting the point behind an object

Hi everyone, I have a problem with making body parts of a "snake" follow the head object.

A picture is worth a thousand words, so here's one:

Here's the code I have:

 public void moveHead(){
         mousePosition = Input.mousePosition;
         mousePosition = Camera.main.ScreenToWorldPoint (mousePosition);
         transform.position = Vector2.Lerp (transform.position, mousePosition, moveSpeed);
         
         directionTransform = Quaternion.LookRotation(transform.position - mousePosition,Vector3.forward);
         directionTransform.x = 0.0f;
         directionTransform.y = 0.0f;
         transform.rotation = Quaternion.Slerp (transform.rotation, directionTransform, Time.deltaTime * 8);
     }
 
     public void moveBodyParts(){
 
         for (int i = 1; i < SnakeBody.Count; i++) {
             **SnakeBody[i].transform.position = Vector2.Lerp (SnakeBody[i].transform.position,
                                                             (SnakeBody[i-1].transform.position-transform.forward*2)
                                                             , moveSpeed);**
         }

and a thread I have used to come up with the erroneous line: http://answers.unity3d.com/questions/722047/get-the-position-behind-an-object-locally-.html

I am pretty sure this is where I mess things up:

 SnakeBody[i].transform.position = Vector2.Lerp (SnakeBody[i].transform.position,
                                                                 (SnakeBody[i-1].transform.position-transform.forward*2)
                                                                 , moveSpeed);

What I aim to do is to move each "circle" to the (previous one's position-it's size*2) where 2 is some arbitrary number that should be the final distance between the two objects.

Would love some pointers on this :) Cheers!