Just a lil' something to do while you shop or wait for someone who's shopping.
This is a Q2SM (quick 2-stage multi).
At the posted coordinates you will see two doors. Use the door on the left and do some math.
Take the first two digits on the door and subtract from 614. This will be the last three digits of the north coordinates.
Take the last two digits on the door and add to 644. This will be the last three digits of the west coordinates.
You Must sign the physical log before claiming a find online.