on the stock exhaust i need to know what are the three components after the manifold?

 

You probably have the original two smaller, pre-catalytic converters, and then the larger main catalytic converter. I just replaced my exhaust, but only the main converter and the muffler were put back in the pipeline.

 

Right after the manifold, there are two resonators then the catalytic converter. So why do you need to know what they are?