I know this is an old thread, but I though I'd show ya how I did mine...
I used an older GM base bracket and made some 'tabs' to attach to the bottom of the bumper.
The 'tabs' are actually shown on there backwards; the plate slips on from the inside of the lower bumper...
I don't even run the front plate here in Calif, I figure if I ever get stopped, I'll tell the cop to "Wait just a second" and put in on at that time. So far, I haven't got stopped for over two years...
Mo

 

very clean! well done!

 

where can i find the battery

 

In the back under the fill panel.

BTW welcome to the site...

Paper chase I moved mine to the lower grill. Using some of them new twistys so I can take it off for shows.

 

what i did was get a strip of 1/2" about 6' aluminum from lowes. on the inside of the bumper there are vertical strips for strength. the 2 inners have a hole in them. i made a c braket to fit in between, drilled in 2 holes. then i made up 2 c brackets with one side longer on the front of the bumper. i drilled holes in the short end to attach to the c bracket i just made for the bumper and made 4 holes for the longer, front side of these brackets. behind then i used lock washers on the bolts for all. i bent these brackets on my vise. u can do it on the steps of a house if need be. just make sure that u tighten the inside bolts up good or the plate will go up & down when u hit bumps. its a tight fit and u may cut up ur hands abit. if u need a pic let me know. i did this in a hurry last winter when i had to register it to park at the train station.

 

OK bear with me, but I took the front license plate off the front of my HHR this morning (prior to my wonderous parking lot incident) and discovered the rivets beneath it. I am a girl who has very little experience with car modifications. How does one drill out a rivet?

P.S. My husband is no help as he has equal the experience of car modification.

 

Drill out the rivets with a drill bit just a little bigger than the rivet shank, drill gentle until the rivet head comes off. push the remaining part of the rivet into the bumper fill the hole with a plastic push pin Sorry I don't know the size of the rivets I think they are 3/8's