Ikea Antonius leg adapter

So I decided to build myself a relatively cheap workbench using Ikea's Antonius line of furniture. I saw that they had a nice little rack system for drawers, a 4 ft table top, and a set of legs and I thought Perfect! Bought two sets of everything planning to make an 8ft bench with lots of storage underneath.

When I got them home to assemble them, lo and behold even though they were from the same system they were not designed to play nice together or at least the way I wanted them to.

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