I decided before I get any ground effects, I thought I would figure out how to take the bumpers off. Its a 91 corolla. I have a haynes book on it but they aren't very graphic. How many bolts hold in a bumper? It talks about the retention bolts too.

I had to replace mine as well. It was so easy.

1= open the boot

2= pull back the carpet

3= remove the plastic panels from the lights (makes it easier to
get to)

4= behind each rear litht you will see two bolds one in front of
the other like this ___:_| ( line on bottom= rear of boot
where lights are, line on the side= side of boot, := the two
bolts)

5= you can loosen the 2 bolts on both sides to adjust the
bumper, or remove the bolts so you can remove the bumper.
One the bolts are removed the bumper will not fall off. It is still
held on by the brackets. At the back of each wheel arch there
may be some screws attaching the bumper to the cover under
the wheel arch. Remove the screws and slide the bumper back.

6= installation is the reversal


See how you go:runaround:
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Leave sooner, drive slower, live longer. Check your auto body parts (http://www.autopartswarehouse.com) regularly.

Boot? Carpet? Please, do explain this. I dont know what you mean by boot, and I didn't know there was carpet in bumpers, since I have never taken them apart before.