Factory Rear Bumper Location/Placement Questions

[BFoley]

I need to fab hitch receiver that doubles as a bumper bracket and I have no idea where the bumper should sit vertically or horizontally in relationship to the box sides and rears. Can anyone provide any sort of dimensional data? Below are pics of the two dimensions I need: 1) bottom of tailgate to top of bumper and 2) gap between bumper and rear of box side.





Once I have these, I can model it up and start cutting and welding.

Thanks,
Ben