I have a '03 JDM STI and also have a full 3" stainless steel 3 piece exhaust system suited for a older impreza lying at home. I understand that the down pipe for the twin scroll is different, is it easy to modify it to fit the twin scroll or would I be better off just splashing out the £200 for a new one?...

The down pipe I have is open neck, if I removed the sandard downpipe + made a copy of the flange that meets the turbo + then cut the flange clean of the decat and got my new one welded on to it. Would that work or am I just making it sound easy?

Let me know what ye think?
Thanks!!