I'm trying to get one of the O2 sensors replaced on my Toytoa Tundra and I need a little guidance. I'm not much of a mechanic. There is a cover on the O2 sensor that has some hidden nuts. Does anyone know what size these are? Also, can anyone tell me a repair manual that has information like this for the 03 Tundra the Chilton manuals I've seen are all for 02. Thanks.