Hi this is Peggy. Here are some instructions on making a bench from a filing cabinet. DIY File Bench | Chelsea Days
Jul 2, 2015 - It's seriously the easiest thing ever, guys, and there are two ways to do it. Step 1: Get a storage bench. Step 2: Rig the Inside for Files. Step 3: Clean Out Your Files.
A quick sketch of what you are planning would be a great idea 😊
How about this? https://www.hometalk.com/11649505/diy-filing-chest-woodworking