Glenn, per your pic, the two red painted bolts below your left tailgate hinge are used to mount the licence plate bracket. My first pic shows these two small bolts at the bottom of the pillar.
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear
My truck ....... Respect The Rust
If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.