If you look at the spec sheet for an auto/comp car the line item is "4GQ M Seat Belts"
Ex:
https://g80.bimmerpost.com/forums/sh....php?t=2003623
I think some cars have them since the allocation dropped from corporate for a comp car, the dealer switched it to manual/base allocation, and the seat belts remained. Just a guess.
edit: I now see your car is on the assembly line and you're looking to add them after delivery. Hopefully my info is helpful for someone else.
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@g80mt on Instagram - 2023 BMW M3 6MT in Individual San Marino Blue / Tartufo
Past BMWs: 2013 BMW 128i 6MT M-Sport Slicktop, 2016 BMW 340i 6MT M-Sport
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