Preheat the oven to 400 F.Wash mushrooms, and remove stems very carefully.Soften cream cheese in the microwave in a large bowl for about 15 seconds. Add sour cream, lemon juice, cheeses, salt and pepper, crabmeat, shrimp and green onions.Heat olive oil in a large frying pan on med-high heat. Add mushroom caps and sauté for 2-3 minutes each side until softened.Line a baking sheet with tin foil and place a wire rack on top. Add mushroom caps, and then spoon filling into mushroom caps.Cook mushrooms in oven on the lowest oven rack for 15 minutes, then switch oven setting on to broil. Switch oven rack to the top setting and broil tops of the mushrooms for about 2-3 minutes until tops are lightly browned.Serve right away, or refrigerate for up to 24 hours and then reheat in 450 F oven for 10 minutes. Filling can also be frozen up to 3 months to refill fresh mushrooms with!