What's the legality of lopping the NEMA connector off of the power cord of a UL-listed appliance and hardwiring it?

Specifically, I have an abandoned 15A 3-phase 208Y/120 disconnect switch that's all hooked up and ready to go- 3 free 120V circuits! Can I just lop the plug off the cord of a 115V power strip (or 3) and hardwire it to 1 phase of the disco switch? And yes, I'm well aware of the "right" way to do it, and there are various (admin & $$$) reasons I'm under pressure to do it with no-cost...