my first option would be to make the insurance company for the owner of the truck fix it.
If that's not viable, then maybe pull the bumper off the car, might be easier to reshape it from the inside.
I've attached a couple of docs from the 03 Matrix manual, and while the body is one difference between Vibe and Matrix, I'd expect the differences in this case are very minor, so they should give you enough info to take it apart and see what's really damaged. One is an exploded view, one is a procedure
Its possible that the bumper reinforcement bar and/or the energy absorber inside are damaged. As safety parts of the rear crumple zone, you'd want to check them out to make sure they're ok
- Matrix rear bumper replacement procedure
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- Matrix rear bumper components/exploded view
- (59.68 KiB) Downloaded 2 times