Your 94 Camry v6 has 3 o2 sensors two are bad -bank one and bank two- does bnk 1 and bnk 2 mean the two before the cat converter- is the one after the cat considered bank 3?

bank 1 sensor 1 is in the exhaust manifold on the firewall side of the engine. bank 2 sensor 1 is in the exhaust manifold on the radiator side of the engine. bank 1 sensor 2 is in the exhaust pipe after the catalytic converter.