I got a huge mirror yesterday (got a great deal on it), and I need some way to hang the sucker. It's not too heavy, maybe 100 lbs, but it's large (about 3.5' x 6.5'). I can't really drill into the ...

A laser level casts a straight line, leaving your hands free to do work. An easy way to align mirror clips is in the shape of a peace sign. Put away your tape measure and let the level be your guide.