Replacing Air Bags

My car was wrecked when I got it and I'm now replacing the air bags, does anyone know for sure about the module..the brain box under the passenger seat? I have the bags but the module is hard to find. some people say that they can just be reset.. other people say they can't, some say all the numbers have to match or the chips between the car and box won't be compatible. I thought that if it was the same year and the bags haven't been deployed it would work. Any help is greatly appreciated!