I need a little help here with finding a glue for plastics, specifically the front license plate bracket.

Here is a quick recap why I need this. I've been driving in Chicago over a year with out a front plate, IL requires a front plate but I took a chance. Last week I was parked at a meeter and when I got back to the car I had a ticket for not having a front plate, appreantly the meter maids can ticket you for this. So I decided to put my front plate back on.

Here is when the problem starts, the OEM from mounting bracket looks pretty bad but as I looked at it I figured if I could mount it about an inch lower and further back it would be much better. So I cut the bracket to the point that it is holding the plate about an inch lower. Mounting it closer to the grill is more difficult. The bracket has posts that will need to be cut off, shortened, then reattached. This is my problem.

What kind of plastic is the holder made of? Is there a glue out there that will bound this type of plastic? Any one who could shed some light on this would be a big help.