The stamped steel benchtop tool bases are great for getting your "new to you" tool up and running without paying through the nose for shipping and handling; however, all the cross members and stuff block using the space under the tool for storing most things. I happened upon some full extension file cabinets and made them into a base for my grinder. I welded them together, made a top, painted it, and bolted the tool on.
Step 1: Meet the Enemy
The old stamped steel base did a great job of supporting the tool and blocking the space under the tool from being useful. Remove your benchtop tool and sell the stamped steel base to someone else.
Step 2: Weld or Bolt the File Cabinets Together
Welding the cabinets together makes everything move around as one piece. This makes it so only four leveling feet are needed. The inner pairs can be discarded. Bolting them together would probably work, but make sure you can support the load of stuff in the drawers without the bolts puckering out the sheet metal.
Step 3: Cut and Install a Plywood Top
I used lots of screws to hold the top on. Take off the drawers to put on the top. With everything on its side it is very easy to put the screws in. Remember this could be getting moved loaded with goodies in the drawers. Moving it loaded may put a lot of stress on the screws and welds. Doubling up costs little, but may save some frustration later. The tool will vibrate which may cause some things to loosen over time.
Step 4: Profit! Paint and Bolt on Your Tool
I wrapped a band of painters tape around the cabinets and then hit it quickly with some combination paint and primer. It is a big face lift for the project, but most importantly IT GLUES THE PLYWOOD SPLINTERS IN where they can't hurt you for the next 20 years.