Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan. Mix together the topping ingredients - brown sugar, chopped nuts and 1 cup coconut. Set aside.
In a large bowl, mix together the flour, sugar, baking soda and salt. Make a well in the center and pour in the eggs and fruit cocktail with juice. Mix well and pour into prepared pan. Sprinkle with topping mixture.
Bake in the preheated oven for 30 to 35 minutes, or until a toothpick inserted into the center of the cake comes out clean.
In a saucepan, combine margarine, corn syrup, evaporated milk and flaked coconut. Cook, stirring constantly, until mixture boils and thickens. Pour over cake and place back in oven for few minutes until it bubbles.