I THINK this is designed to work without a harness bar right? I can't remember exactly what they claim but I have the exact same harness setup in my car right now. I've used it once on the track and it worked extremely well.
2010 Porsche 911 GT3 (Carrera White/Black)
2010 BMW e92 M3 M-DCT (Frozen Grey/Black) - Sold
2007 BMW e92 M3 6MT (Jerez Black/Palladium Silver) - Sold
2002 BMW e46 M3 SMG (Titanium Silver/Black) - Sold