Grilled Salmon with Herbs

This recipe comes from a cookbook The Weight Watchers Complete Cookbook & Program Basics, 232. I tried to find it on the web because I just have a copy of the page I think I just copied the pages that I liked and got rid of the cookbook but I have used this recipe probably a dozen times and it always tastes great. Some slight variations from recipe -instead of butter I use olive oil, also I chop the rosemary and thyme and add it to the rub of the fish.
One 10-ounce salmon fillet
2 teaspoons reduced-calorie tub margarine
1 tablespoon fresh lemon juice
2 tablespoons minced fresh parsley
1/2 teaspoon garlic salt
1/2 teaspoon paprika
1/2 teaspoon freshly ground black pepper
3 or 4 sprigs fresh rosemary
3 or 4 sprigs fresh thyme

1. Spray grill rack with nonstick cooking spray. Place grill rack 5" from coals. Prepare the grill according to manufacturer's directions.
2. Place salmon fillet on double sheet of heavy-duty foil, leaving a 6" border. Fold up edges to make a foil pan.
3. Spread both sides of fillet with margarine; sprinkle with lemon juice. In small cup, mix parsley, garlic salt, paprika and pepper; sprinkle both sides of fillet.
4. Drop rosemary and thyme sprigs directily on coals. Place foil pan containing fillet on rack. Cover grill. Opening top and bottom slightly.
5. Grill fillet, covered, 15-20 minutes, cooked through and flesh flakes easily when touched with a fork. To serve cut fillet into 4 equal portions.