Heat gas or charcoal grill. On each of two 12-inch metal skewers, thread shrimp, leaving 1/4-inch space between each shrimp. Brush with oil. Sprinkle with 1/8 teaspoon salt.
Cover and grill kabobs over medium heat 4 to 6 minutes, turning once, until shrimp are pink and firm. Remove shrimp from skewers.
On 2 serving plates, place lettuce. Top with celery, bell pepper, tomatoes and grilled shrimp.
In small bowl, mix all dressing ingredients, adding enough milk for desired consistency. Spoon dressing onto centers of salads.