Well gosh darn, silly me......
I had thought, just maybe, this was not the first person who asked about replacing the chrome exhaust rings.
Yeah, silly me......
Current debate is between removing the axle-back section of the exhaust or removing the black plastic portion to easily r&r the exhaust trim rings.
You don't want to remove the complete rear bumper assembly unless you absolutely have to!! It has many many interlocking tabs connecting to body sheetmetal, which, by all reports, will mostly break unless you're very lucky or very skilled. The skilled ones who have been there done that will tell you to try alternatives first.
But, you know, I'm just guessing, since I've never done this, and we've never posted about it.