On the SEL, there are four bolts per side, I think 18mm. Access from below, then pull the bumper straight off - without doinking it off your head, feet or the ground.
The chrome inlay is held in place by about a dozen bolts, 10 or 11mm if memory serves me correctly. These can be accessed with the bumper on the chassis but it's much easier and faster to do this after taking the bumper off, as the small bolts each have a washer nut. You'd have to have angelic patience or be pretty stupid to complete this job with the bumper still on the vehicle (don't ask me how I know).
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