For Corsair, first make sure the angle iron ledges are installed inside the firebox. Insulation and firebrick should also be installed before grates. Place the grates in the center of the firebox as shown in the photos. Note that the orientation of the grates is different in StarCat/Dauntless compared to Corsair. Optional: You may fill the V’s with sand. This can help increase the lifespan of the product.