I printed this in PLA using the fastest mode in Cura.
Step 1: Hammer in shelf supports
I faced the rounded section down. They should hammer in quite easily.
Step 2: Insert brass inserts
I used a soldering iron. There are four holes - just pick the two that fit depending on orientation of your drawer runners.
The screws just stop the drawer runners from coming out when you pull the drawer.
Step 3: Cutout holes for the bins using a jigsaw
I used the existing shelf.
Step 4: Screw the drawer runners to the shelf.
Just makes sure you get the runners the right way around!