Drilled a 1/4" hole (using a round drill bit) with the drawer closed, using tape, to mark out the level of the side of the drawer and another piece that was cut to the depth of the front of the drawer, so the hole would be down a decent amount and back a decent amount.
Removed the drawer, then used a flat 3/4" drill bit to enlarge the 1/4" hole in the side of the Alex Drawer unit. (drilled from both sides, to avoid splintering the wood.
I also widened the hole in the drawer a little bit more then 1/4th, by reaming it with a flat 1/4th wood bit, so the plunger wouldn’t stick as much.
uxcell® Push Plunger Lock, 3/4-inch Diameter 23mm Long Cylinder, Keyed Different(Pack of 2) Not keyed alike