Mince and mash Garlic in a Mortar and Pestle. Place in Blender with Fresh Lemon Juice and Black Pepper until smooth. With motor running, add oil in a slow stream, blending till emulsified. Transfer dressing to a bowl and add in your chopped FRESH OREGANO.
Prepare your GRILL (Moderate Heat for GAS and Direct Heat with Med-HOT Charcoal.
Toss Shrimp with 1/4 Cup Dressing in a Large Bowl and marinate NO more than 15 minutes(Texture of Shrimp will change if marinated longer!).
Brush Lemon wedges with some of remaining dressing and grill till marks appear (approx 5 minutes) then transfer to large patter.
GRILL shrimp on lighlty oiled Grill Rack, turning over once till cooked through approx 8 minutes total Transfer to platter with Lemons as grilled ~ Top with remaining dressing!