I taught this box in my recent classes and they wanted a video tutorial and this is the best one out there. Hope you enjoy and this is a fellow demonstrator Liz Holloway so I thank her for doing the video.
GW here is the bottom measurements. I am not sure what happened to the end of the video and I am not set up to do video but here are Liz's measurements for the bottom
Cut paper at 5 3/4 x 5 3/4 Score on the diagonal score at 1 3/8 2 7/8 and 4 3/8 dont forget to remove the plate and score from 2 7/8 down the small diamond from top to bottom of diamond on all 4 sides
the insert measures 1 7/8.