Heat oven to 375°F. In large bowl, combine sugar, margarine and vanilla; beat until light and fluffy.
Lightly spoon flour into measuring cup; level off. Add flour and salt; blend well. Stir in 1 cup of the chocolate chips. Cover with plastic wrap; refrigerate 15 minutes for easier handling.
On lightly floured surface with lightly floured hands, roll dough into 7-inch ropes about 3/4 inch in diameter. Place on ungreased cookie sheets; shape ropes into letters. Some letters may be smaller or larger than others. To make letters all the same size, add or pinch off small pieces of dough.
Bake at 375°F. for 10 to 13 minutes or until edges are light golden brown. Cool 1 minute; carefully remove from cookie sheets. Cool 5 minutes or until completely cooled.
In small saucepan, combine remaining 1/2 cup chocolate chips and shortening. Melt over low heat until smooth, stirring constantly. Drizzle in striped pattern over cooled cookies.