Not sure I understand description of problem and don't know what model and year you're driving but bumper removal is pretty simple on my '97.
Remove fasteners at wheel well covers, remove 4 nuts at rear of car and slide bumper backwards off of mounting studs. From your description I get impression the blow to bumper has knocked it back and off pass side mounting stud.
When you get bumper off you should take the oppurtunity to add sealant around air vents (known culprits for water leaks into trunk).
98 Mystique LS v6 atx 110,000km
97 Contour LX v6 atx 125,000km
stock CD on LS, cass on LX
spoiler, tinted windows on LS only
4 wheel discs on LX only
All other available options on both
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