Drawing line from plane edge

I am trying to draw a line from one object to a target object. i have managed to do this however the lines are drawn from the centers

what i would like to do is draw the lines from the edge of a plane to the edge of a plane on the target

Imgur

In this image the white lines are the currently drawn connection and the red lines are how i would like the lines to be drawn

Maybe this helps:

Attach this sctript on the plane

using UnityEngine;
using System.Collections;

public class GetBounds : MonoBehaviour 
{
	Vector3 targetPoint = Vector3.zero;

	public void OnDrawGizmos()
	{
		Mesh mesh = GetComponent<MeshFilter>().mesh;
		Bounds bounds = mesh.bounds;
		
		// not affected by scale or rotation
		Debug.Log ("x: " + bounds.size.x +" y: "+ bounds.size.y + " z: " + bounds.size.z);
		
		// next you can simply calculate the start point of the ray
		Vector3 edgeA = transform.position + new Vector3(bounds.size.x * transform.localScale.x / 2, 0, 0);
		Vector3 edgeB = transform.position - new Vector3(bounds.size.x * transform.localScale.x / 2, 0, 0);
		Vector3 edgeC = transform.position + new Vector3(0, 0, bounds.size.z * transform.localScale.y / 2);
		Vector3 edgeD = transform.position - new Vector3(0, 0, bounds.size.z * transform.localScale.y / 2);

		// next if plane is rotated you must calculate position for this rotation...
		edgeA = RotatePointAroundPivot(edgeA, transform.position, transform.localRotation.eulerAngles);
		edgeB = RotatePointAroundPivot(edgeB, transform.position, transform.localRotation.eulerAngles);
		edgeC = RotatePointAroundPivot(edgeC, transform.position, transform.localRotation.eulerAngles);
		edgeD = RotatePointAroundPivot(edgeD, transform.position, transform.localRotation.eulerAngles);

		Gizmos.color = Color.red;

		Gizmos.DrawLine(edgeA, targetPoint);
		Gizmos.DrawLine(edgeB, targetPoint);
		Gizmos.DrawLine(edgeC, targetPoint);
		Gizmos.DrawLine(edgeD, targetPoint);
	}

	private Vector3 RotatePointAroundPivot(Vector3 point, Vector3 pivot, Vector3 angles)
	{
		Vector3 dir = point - pivot; 			// get point direction relative to pivot
		dir = Quaternion.Euler(angles) * dir; 	// rotate it
		point = dir + pivot; 					// calculate rotated point
		return point; 							// return it
	}
}

It looks like this:

http://s13.postimg.org/h1cz5vfyf/bounds.jpg