Just looked at the diagrams, it appears the I-6 exhaust exits the dual cats/resonators with different spacing from the V8, and the pipes I'm sure are different diameters. You'll need a welder to match up the pipes.

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2009 E70 N62 Titansilber Sport
2000 E38 M62 Schwartz II Sport
1997 E36/5 Schwartz II M-Sport (gone)