The catalog number "KECH-8005~48" isn't mentioned anywhere on the box, only "KECH-8005". The discs themselves have catalog numbers starting from KEC
X-8005 to KEC
X-8048.
The only site that mentions "KECH-8005~48" is the official site for the box, but it is not printed on the physical product.
Edit: The previous tracklist was missing one track from disc 43, so I had to add a new tracklist. Please delete the previous one. Scans will be up when I have time to convert 83 images to jpg.
Edit 2: All the scans are uploaded now. The lyric cards were digital only, that you were able to download with the code given in the art book. Nothing else is sadly possible to scan for me, since I don't own an industrial size scanner. The box is made of a hard material, so it's impossible to bend into a scanner, and if I tried to scan it with my scanner, it would just yield extremely blurry images. I took some pictures of the box, CD book, art book, and USB, if anyone is interested.
https://imgur.com/a/8Bfr3
Oh, and the image called "Box", that is simply the wallpaper that was available to download together with the lyric cards.