7$ river action

No Limit Holdem Tournament 2 Players Hand converted by http://husng.com/converter $6.67+$0.33 BB Hero 1515 SB CloseTwin 1485 Effective Stacks: 50bb Blinds 15/30 Pre-Flop (45, 2 players) Hero is BB with s8 d8 CloseTwin raises to 60, Hero calls 30 Flop (120, 2 players) d4 s4 d6 Hero checks, CloseTwin bets 60, Hero raises to 180, CloseTwin calls 120 Turn (480, 2 players) s7 Hero bets 270, CloseTwin calls 270 River (1020, 2 players) sT Hero ???Now i know 100% that i`m ahead here, villain is opening 70% of his buttons and is super weak postflop. The question is how much should i bet on this river to get a call from a possible 6 given the fact that he is not that retard to call a shove with just a 6.