Preheat grill on HIGH 10 min.
1.Clean grill with wire brush. Using soft cloth, coat grill grate lightly with vegetable oil.
2.Combine papaya, green onions, lime juice, jalapeno, and cilantro in small bowl; set aside.
3.Toss arugula with lemon juice; drizzle with olive oil. Divide equally on 4 plates.
4.Season both sides of fillets with salt and pepper; drizzle both sides with basting oil (too much oil will cause flare-ups). Sear fillets on grill 1-3 min, until they have changed color about one-quarter of way up from bottom. Turn over; baste (brush seared side with basting oil). Sear 1-3 min.
5.Turn over; baste. Cook 1-3 min. Turn over again; baste. Reduce heat to MEDIUM; close cover. (Cook fillets1 inch thick or less 3-4 min/side on MEDIUM; cook fillets 1 inch or thicker 5-6 min/side on LOW.
6.Cook until internal temp reaches 130 degrees; check by inserting thermometer into thickest part of fillet. Transfer to clean platter; let rest at least 2 min.
7.Place on arugula. Top with papaya mixture.