Mix crab meat, shrimp, 1/2 of salsa and 1/2 of the Alfredo sauce. Set aside leftover salsa and Alfredo sauce.
Take burrito shells and slice a piece of the processed cheese and lay it in the burrito shell. Then add crab mixture. Roll up like a burrito closing both ends and repeat until mixture is gone. Place them side by side in a 13x9 dish. Pour the remaining salsa and Alfredo sauce over them and then sprinkle on the cheddar jack cheese.
Place in a 350 degrees F oven and bake for about 30 to 45 minutes. Top with sour cream and shredded lettuce before serving and enjoy.