Mix together marinade for shrimp: oil, salt, pepper, garlic, and cayenne or paprika. Toss shrimp in marinade and let flavors meld.
Cook bacon to desired level of doneness, preferably in cast iron pan. Remove to paper towel lined plate and reserve 3 tbsp of the rendered fat.
Bring 4 cups of the stock to a boil. Turn heat to medium. Slowly pour in grits, stirring constantly. Continue to stir for 5 minutes. Turn heat to low and cook, stirring occasionally, adding more liquid as grits become firm, until all 6 cups have been used. Cook stone ground grits for 45-60 minutes and quick grits for 20 minutes.
Once grits are creamy and all liquid is absorbed, stir in 2 Tbsp of bacon fat, butter, and soy sauce. Add salt and pepper to taste.
Heat remaining bacon fat in cast iron pan over medium-high heat (same pan used for bacon is fine). Once hot, add shrimp in single layer (cook in batches if needed). Cook for about 2 min per side, or until tails curl and flesh turns opaque. Remove immediately.
Divide grits into 4 bowls. Top each with shrimp. Crack one soft-boiled egg into the center of each bowl. Top with bacon and scallions. Add salt and pepper to taste.