I'm kind of flitting about here, busy day.
To follow up - IIRC, if it's actually the bumper skin that's the main issue, front or rear, you can slot/notch the mounting holes that use the pop rivets, slide some washers under those points, and button it all back a smidge more tightly with no gap.
Should be a couple DIYs for that still kicking around on here.
Will take pics if/when I do this.
We need a bit of a Renaissance on here to replace a bunch of the threads that have lost their info and/or pics.