Expanded metal over your windows will be less expensive than a SureFire weapon light, but if your need is great enough to justify the cost, and if you can find one for a Defender, a SureFire forend is I the way to go. I have a Fenix flashlight that came with a pressure switch, that I mounted to my Sidesaddle. But its a battery hog; every time I need that thing, the batteries are dead, and we do have bear issues when its dark. As to light mounting solutions, the challenge with the Sidesaddle light mount is keeping the thing tight, so short of a Surefire forend, I'd now recommend a pic-rail mount on the forend and a flashlight with a 1" barrel that can be secured to the pic-rail with a scope ring.