Open the pork by the belly, but do not cut or poke holes into the upper or side skin. Place the grease tray inside the Caja China. Tie the pig in between the grids, on its back, and place in the grease tray. Close the Caja China with the ash pan and charcoal grid. Allow 4 inches of separation between the roast and the ash pan. We recommend the pork be at room temperature at the time of roasting.
Prepare the charcoal: we recommend Kingsford Charcoal because it lights faster, burns evenly, and lasts longer. Never use instant charcoal. Start with 14 pounds of charcoal for Caja China Model #1 and 16 pounds for Model #2. Place the charcoal into 2 piles of equal size, on each end of the charcoal tray. Never place charcoal on center of tray. Add lighter fluid and light.
When the charcoal is lit for 15 minutes, distribute it evenly throughout the tray. Once this process is completed, roast pork for 3 hours, without opening the Caja China. Add more charcoal after 1 hour and distribute evenly throughout the tray. After 3 hours, wearing heavy-duty silicone mitts, remove the charcoal tray, ash pan, and dump the ashes. Then turn the pork over and cut into the skin, every 4 to 6 inches. Place the ash pan and charcoal tray, filled with new charcoal, back into position and continue the roasting process. Check the skin after 20 minutes, slightly opening the box by 1 of the corners. You can continue this process until the skin's crispness is to your liking. For a pig this large, it will probably require a full hour on its second side.
Remove the pork from the Caja China. Deposit the contents of the grease tray into a container, let cool, and discard with trash. You can slice the pork with a plate; it is not necessary to use a knife.