In a large saucepan, combine sugar, water, corn syrup, vinegar and salt. Bring to full boil, stirring constantly. Boil 3 minutes without stirring. Remove from heat; cool 5 minutes. Add chocolate morsels; stir quickly until melted. Stir in pecans. Quickly drop by measuring tablespoonfuls onto foil-lined cookie sheets (work as rapidly as possible as mixture tend to set up quickly). Garnish with pecan halves,if desired. Refrigerate until set (about 20 minutes). Peel candies off to serve. Store in refrigerator. Makes 4 dozen 2" candies. Toll House Heritage Cookbook, Rev. 1984. From Tony Balano.