Kalil, good shots. You know what I ended up doing, though? I plugged the relay output and paid a muffler guy $50 to slice off the pipe with the flap, remove it and weld it back on with a small connector to keep the length right. No mechanical worries, now. Car sounds great.
2007 E92 335i . Space Grey . Premium . Sport
2006 E85 M Roadster . Alpine White . 6MT
2006 E60 550i . Sapphire Black . A5 . Sport . Premium
2003 E39 530i . Titanium Grey . 5MT . Sport . Premium
1989 E34 535i . Black . A4 . Premium . RIP
1981 E28 530 . Grey . A4 . German Specs . RIP '94 in USAREUR
1977 E21 320 . Light Blue . 4MT . German Specs . RIP '92 in USAREUR