Found a place that sells a "kit" for building your own floor scale. My kit can handle 20K. The kit has all the guts you need, I need to provide my own platform. They recommend 3/4 or 1" aluminum. ...
Be a great stocking stuffer if only we hadn't replaced the kitchen in the homestead last month. You'll make a lot of friends at a Rally even if you charge a fee. Couple of dollars a tire would be reasonable.