Standard 172 Ph1 exhaust help

[skini]

Can you tell me how does exactly look exhaust system on 172 Ph1? Maybe somebody got some pic of cmplete exhaust??

Is it: 4-1 manifold, lambda, two parallel cats, lambda, pipe, backbox ??

 

[skini]

Does it have two cats and no center silencer? Just wanna know to see if my 172 has standard exhaust, or previous owner did some changes!