Pay Attention, Dummy!

I made a mistake.  First, the excuse - it's been a rough month, I'm tired, and I'm fighting a head cold.  Now onto the mistake.  Look at this first photo.  Notice the frames around the windows, inset into the siding?

Now, look at this next photo, paying particular attention to the window on the left.

When I installed the siding, I forgot to leave room for the window frames.  Using an Xacto knife and a couple of needle files, I was able to carve out the necessary space, as you can see with the window on the right.  It all worked out in the end, but with a lot more effort than necessary.