helix now makes an uppipe/downpipe combo thats prefabbed for ewg. i know people have been unhappy with the placement of the ewg when they try to dump it but apparently if you get both pipes and plumb it back in its supposed to fit well. they're quite cheap too... just a fyi if that helps speed up your plan
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and imo, if you're going to do an upgrade, you might as well do an upgrade... green or 30r are the way to go