Fusion360: Consistent width finger joints

I recommend viewing the newer video at https://youtu.be/XoDbBkgv33U after viewing this one. A newer version of this model is now available at https://www.thingiverse.com/thing:2839125 In this video I design an open-top box with finger-joints for cutting on my Glowforge laser. All of the fingers in this model are consistent in width, and the number of fingers automatically adjust based on the dimensions of my model.