Cut limes in half and squeeze juice in a 2-cup glass measure. Add vinegar, vegetable oil, soy sauce and honey. Peel and mince garlic and add it to the measure. Add red pepper flakes, if disired. Whisk mixture well to blend in the honey.
Combine the soy sauce, bourbon and brown sugar. Add tenderloins and marinate for up to 3 days. Cook on the grill 20-30 minutes. Combine the remaining ingredients to make the sauce. Slice the pork and serve with the sauce. The meat is good served warm or at room temperature.