draw canvas/2D space Box Colliders on top of 3D objects that are located in world space?

  **Is there a way to draw 2D Screen/Canvas space box colliders on top of 3D space objects depending on how far away they are from the camera and how much space(in pixels) they occupy on screen? I have managed to do something close to that but it doesn't represent proper shape of an object from different perspectives. Here are some of my reference pictures but with blue lines added in photoshop to help you better understand what I'm intending to do:![alt text][1]![alt text][2]**

If you help me with this I'll be very grateful thanks.