just recently, I was looking to get a granite surface plate. I figured that I would get a 18 x 24" plate , remove the rear lock plungers and housings on my 5 drawer unit, and it would sit very nicely in the top box. Everything measured out just right. Add the snap on hinges, and the lid goes vertical and out of the way. That cart would be dedicated to Metrology instrumentation and then get another for regular tools. It sure would be a good place for one if You are not too worried about thermal expansion differences between top and bottom of the granite.
However, things change, and the Wife talked me into getting a 24" x 36" surface plate with stand. Now THAT was strange!