No bondo.
Use Flex-weld, Duromix, SEM Bumper repair kits, or a Thermo-plastic such as plastic-weld.
You want to sand the bumper down with 200-400 grit. or Use a Heavy-grade 3M Scuff pad.
Apply the 2-part A/B Mix... with a putty wedge.
Sand.
Repeat
Sand
Repeat
do this until area is smooth.
Finally prime, sand, apply more stuff if needed, and repeat.
This was a 6 month Project from Start to finish, many hours of work, mostly 1-2 each weekend, 1 or 2 days a month... so it was slow moving.
If I did it again with the bumper in my garage, I could do it in about
~16-24 Hours of work.
The below was ~ 40-60 hours of work, just cause it was my 1st time doing such a project.... (~$180 in materials, paint, supplies.)
I was actually thinking of selling it -- We'll see....
Project Pics:
It's a Fun Project!
I'd do it again, if I had the time... Or if I was paid.. haha.
and I'd shave that license plate recess...