catback question

Hoping that someone can help me out with a question. Will the GHL catback for the gti fit wit the other stock components? Or do I need to buy an aftermarket downtime?

Why did you post this question in the 2.5L Golf section? It belongs in the 2.0T section. And did you mean downpipe? If so, don't know about the specific catback you're talking about, but I'm pretty sure all the other catbacks for the MK6 GTI work with stock downpipe.