You know I completely forgot about those little guys! I used those for my first set of backup lights!
Our prototype shown down below during fab was about 4½" out from the end of the receiver itself, I didn't really look at how far it stuck past the v2 bar... But I would say it was about 3" past.
With that said, our production model will only stick past the receiver approximately 3", which will mean on a V2 or similar, it should only stick past about 1-2", but I can grab some measurments once I have a production model built.