If your cake pans are 9x1 1/2 rather than 9x2, you can use them anyway, but leave behind about 1/3 cup of the batter so that the cake won't rise over the top.
The frosting came together nicely. I used a thick, nonstick, black saucepan rather than a metal pan, so the sugar took a little longer to melt, but the candy came to 235 at a nice, even pace. The most difficult part of the recipe was knowing just when to pour the caramel onto the cake. I needed to be soft enough to spread out, but cool enough to set.