Supreme the orange. Remove skin and pith and divide into wedges, set aside.
Squeeze a little lemon juice on shrimp and scallops; toss them lightly in flour. Set aside.
In a sauce pan melt 2 tablespoons of the butter. Once the butter is melted and bubbles start to subside, add shallots and cook until tender, about two minutes. Add garlic and cook until fragrant, about 30 seconds.
Pour vermouth over shallots and garlic, bring to a simmer and reduce by ½. About 3 minutes. jAdd orange juice and simmer until reduced by ⅓, about 5 minutes. Add the heavy cream and simmer for about 10 minutes. Set aside and keep warm.
In the meantime, cook the fettuccini noodles according to package directions.
When the pasta is well underway cooking, heat a large skillet over medium high heat. Add the remaining 2 tablespoons butter. When the butter is hot, add the scallops, standing up. Brown the scallops, this will take 2 - 3 minutes and then with tongs, turn them over. Then add the shrimp. Cook until the shrimp are golden brown and the scallops are cooked through. About another 2 - 3 minutes.
Drain the pasta and return to pan. Pour the orange cream sauce over the pasta and with tongs, turn to mix well.
To serve, place the pasta into your favorite pasta bowls and top with the scallops and shrimp dividing them evenly between the bowls. Sprinkle on the orange slices and chopped basil.