Preheat oven to 350F. In a large saucepan, melt the brown sugar, syrup and butter together with the bourbon, vanilla and salt. Continue heating the mixture to the boiling point, stirring frequently. Boil for 1 minute, stirring constantly. Remove pan from heat and let mixture cool. In a bowl, beat the eggs with the half-and-half until they are light and frothy. Add to the cooled syrup, beating until the mixture is well incorporated. Stir in the pecan pieces. Pour the filling into the pie shell. Top with a layer of pecan halves. Bake 45 to 50 minutes until a toothpick inserted into the center comes out clean.