I found a local laser cutting shop in town that was able to cut the grate for $75. My brother is an engineer and ran some simulations to make sure it would be able to support weight (this particular grate will support 750lb and is a 23"x23" square- 3/16" thick A36 steel). Let me know if you want the .DXF file.Awesome! I've started thinking about doing the same thing when I go to build my riser. My 2nd tier will be tall enough that I could fit a full marty laying down inside of it. I figured the row of seats would be above the driver, and the port would be behind them, so no risk of people walking on them. The grate still seems like a good idea though. Where did you find the grate? Or are you building it?