Can I use a complete stock exhaust system from a 2003 cobra to replace my 2004 v6 exhaust?
Yes, but some different dia, adapters & Y or X pipe might be needed? Consult an exhaust shop. Sometimes they can make you the parts. Example, a 2" V6 pipe adapter to a 2 & 1/2" or 3" duel Cobra pipes, see? Scrap the V6 cast iron exhaust manifolds for tube headers, they have bigger collector ends, this aftermarket add-on might be worth looking into.
Search Ford Mustang Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Ford Mustang Experts