Question about old-style locking mechanism - Knaack job box

[Scott 730]

It's not obvious to me from the tag below how the lid actually locks,

Ignore your tag and look at my pictures. It is only showing how to mount the padlock.

The piece of flat stock with the notch drops into the open lock shackle as the lid is closed. The lock is pushed shut which pushes the notched flat stock so the notch is trapped by the shackle.

 

[timsch]

OK, that adds up. I'll need to get/make the flat notch piece. I suppose that the notched piece (NP) is mounted on those triangular brackets shown in my 1st pic. I'll need to get some dimensions for that.

Getting closer now. Thanks Scott.