I think the E46 330 headers for M54 need to be used as they have dual o2 ports -

Performance Exhaust Manifold Headers Fits BMW E46 E39 Z4 01 06 2 5L 2 8L 3 0L L6 | eBay

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2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards