on my car i have the original top part of the downpipe with the factory flange still on my car hooked to the manifold and the u bend and cat are deleted and welded to where the resinator used to be. Ive got headers ordered from autochrome just waiting for them to arrive. What will I have to do cut part of the exsisting down pipe off and clamp it to the pipe where i cut? I plan on having them welded down the road but for now im just gonna clamp them with clamps i got from zzp. Thanks for any help!