The pit should be constructed 12 to 24 inches from the fire to the grill. The advantage of this distance is that it provides more even heat distribution. An easy way to build a pit is using concrete blocks (8 inch) and laying the blocks two high. Build the pit 3 to 4 feet wide (inside measurements) and as long as needed. Lay metal rods across the cement blocks and place a suitable wire or screen over the rods.
Published by Skyhorse Publishing, New York City.