It turns out that stacking washers and dryers had to be the same brand, because there's a kit of some sort that connects them. Who knew? Anyway, I now have an LG washer and a Frigidaire dryer, and they won't quite fit side-by-side in my laundry space. I can either knock out a wall, or figure out some way to secure the dryer to the washer.
I'm thinking that a couple of metal braces and sheet metal screws should do an adequate job. The dryer feels like it's pretty stable to begin with. Thoughts?
Oh yeah. At one point, the installer asked me if there was any chance I had a screwdriver he could use. I just laughed and grabbed the one that was within arms reach at the time.