It looks like the aluminum base has been crimped around the red plastic part and you will likely destroy it getting it apart.
I'd throw it away.
Use a hammer
Why not drill numbers of holes into the aluminum base you need for the lights then fill the holes with silicone when you are done .
It's a nice reflector. It would be a shame to destroy it to make a poor light (reflector and light lens optics are different). Keep the reflector, and make or buy a light.
An ounce of diagnosis is worth a pound of cure.
“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
thanks for the advice
There's no such thing as a routine repair.
Don't tell me what "should" be - either it is, it isn't, or do something about it.
If you think I'm being blunt take it as a compliment - if I thought you were too weak to handle the truth or a strong opinion I would not bother.
Please take the time to post clearly so we can answer quickly. All lowercase and multiple typos makes for a hard read. Thanks!
Before you do anything, see if you can find a type of light that would fit in there; looks to me too small for any kind of light and battery system to fit inside. You might consider an external battery, so that would require drilling the aluminum base for the wires anyway.
Decent LED taillights are so inexpensive and so much better than jury-rigging your reflector that it's not worth the time or cost to modify it.
They are self contained, run on AAA batteries that last a long time and have both steady and slashing modes. This one is only $7 and is better than anything you could make: http://www.nashbar.com/bikes/Product...42_-1___202551 For a bit more money you can get a super bright taillight that can be seen for blocks.