Pat shrimp completely dry with paper towels
If using wooden skewers, soak in water 30 minutes
Whisk melted butter, olive oil, garlic, and lemon juice in large bowl
Add paprika, garlic powder, onion powder, oregano, black pepper, cayenne, and salt to marinade
Add shrimp to marinade, toss to coat completely
Cover and refrigerate 30 minutes (max 1 hour)
Preheat grill to high heat (450-500°F), clean and oil grates well
Thread shrimp onto skewers, piercing through tail and head so they lie flat
Reserve leftover marinade for basting
Place skewers on hot grill, cook 2-3 minutes without moving
Brush with reserved marinade, flip, cook another 2-3 minutes
Shrimp done when pink, opaque, and slightly charred (total 4-6 minutes)
Remove from grill, let rest 1 minute
Brush with any remaining marinade, sprinkle with parsley
Serve with lemon wedges