Front Bumper Mounting?

[72 F-350]

I have a 1972 F-350 Chassis Cab (10,000# GVW, 360, 4-speed) that didn't have a front bumper when I bought it. I was looking a the pictures trucks being restored, and noted that the frames were made so that the bumper bolts right up to it. My truck has a straight frame that is not curved for the bumper. Was my frame modified or were trucks like mine made differently?

[FORDification]

The bigger trucks had bolt-on front bumper brackets, like this:



I'm not entirely sure how they figured out who got this, but I'm sure someone else here can fill in the details.

[72 F-350]

That's exactly what my truck is missing. Does anyone have any they would want to sell?