Soak corn husks in hot water overnight, to soften.
Filling
Combine pork and water; simmer 35-45 minutes, or until very tender. Drain, reserving broth. Break meat into coarse shreds.
Cover dried roasted chiles with boiling water; soak 20 minutes. Drain chiles; place in blender jar. Add oregano, cumin, coves and 1 cup reserved pork broth.
Blend until smooth. Add additional broth if desired; blend to desired consistency.
Cook onion and garlic in lard until tender. Add meat and salt, mixing until blended. Stir in chile mixture; simmer 15 minutes.
Masa
In large bowl beat lard until fluffy.
Combine masa harina and salt; alternately add masa harina mixture and broth to lard, mixing well after each addition.
Gradually beat in melted lard, mixing to consistency of thick cake batter.
Assembly
Spread 2 tablespoons masa in center of each husk.
Spoon 1 tablespoon meat filling lengthwise down center of masa.
Fold husk over filling, allowing plain part of husk to wrap around tamale. Fold bottom end up over enclosed filling.
Steaming
In steamer or 4 qt. Dutch oven, place rack 2" above gently boiling water. Arrange tamales upright in steamer basket. Do not pack tightly. Fill in spaces with extra corn husks to keep upright.
Cover top of tamales with corn husks; cover and steam for 2-2-1/2 hours or until tamales are firm and fall away from husk.