The piping is made from a separate strip of leather, which is sewn onto the main piece that's covering the front of the glove box door.
This is similar to what's shown in the middle diagram from your examples. The only difference is that the main door covering leather
section is trimmed off just behind the stitching and is not wrapped and tacked around the rear face of the door. Also the piping leather
is skived down to the minimum so that the two layers tacked to the rear of the door are only 1mm thick. Due to this section being so
thin there wasn't any need to pad under the inner covering board.
I posted some photos of an original 289 glove box door in an old thread here.
https://www.acownersclub.co.uk/forum/index.php?topic=2878.msg22632#msg22632I hope the above helps,
Luke.