A barbecue spit is versatile in that you can roast a whole pig or large chunks of meat. The meat slow cooks over the coals--depending on the size of the whole animal or chunks, it could take 12 to 15 hours. Be prepared to take turns with your friends turning the meat as it cooks. If you prefer to use a marinade instead of a rub, you also need someone to brush the meat every half-hour or so.
Dig a pit 2 feet deep, 4 feet in depth (front to back) and as wide (lengthwise) as you prefer. One of the stainless steel rods needs to fit across the width of the pit, plus 2 feet on each end. Line the center of the pit with 2 inches of sand, leaving 1 foot on each of the long sides and 2 feet on the ends of the pit bare.
Pound two of the 1-inch diameter stainless steel rods 2 feet into the ground at each end of the pit. The rods must form an X. The cross rod rides in the top of the X. Angle the rods closer to the ground to make a lower spit. The larger the angle, the taller the X is, and the higher off the fire your meat will be.
Line the cement blocks along the ground, between the rods that create the bottom of the X. The blocks help support the rods so the weight of the meat does not force them down. If you build the spit in soft soil, such as sand or loose loam, the blocks are required, but if you build the spit in heavy soil, such as clay, the blocks are optional but recommended.
Build the fire in the pit, off the sand. The easiest way is to make four piles of kindling--one on each side of the pit. Add water-soaked hickory wood (it should be soaked for at least 24 hours) to the fire, lining the wood all the way around the perimeter of the sand. Allow the wood to start burning well.
String the meat on the cross rod. Lay the cross rod in the X supports. Clamp the vice grips on each end of the rod. Turn the spit by pushing the vice grips.