We used a heavy piece of aluminum angle, stainless steel u-bolts and the front brace from our old Force-10 grill to mount the grill. This give a much more rigid mount than those offered by the typical Marine grill manufacturers.
All in all, this is the best, and least expensive, grill we've ever had on the boat and we've had several manufactured by Magma and Force-10.
We also purchased a heavy guage stainless steel fish/vegetable grilling tray from Home Depot for about $12.00 that fits perfeclty inside our grill.