The OEM is a 2-piece unit (or mine is unless it wasnt standard), whilst the SHP is a 3 piece unit; main back box, 'long' pipe, mid silencer.
In order to get the OEM pipe on, you'd have to do a cut and shut job which in turn make the OEM unit a 3 piece unit....
You could go to a exhaust fabricator and get another mid pipe made i guess but probably wouldnt be the same material as the HKS one, mind you, not many people are going to see it though.
As for Edward polishing his exhaust :roll: :roll: :roll:
Just reread you post mike, do you mean just mate the HKS back box to the OEM mid-section/silencer?