Normally, for gxp road cranks, the bb shell is 68mm, and you just use the cups without the spacers.
http://www.sram.com.cn/sites/default/files/techdocs/RED%20Crank%20BB%20PRINT.pdf
You should have got that, or something similar with your exceedingly expensive cranks.
@user64361 started
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Normally, for gxp road cranks, the bb shell is 68mm, and you just use the cups without the spacers.
http://www.sram.com.cn/sites/default/files/techdocs/RED%20Crank%20BB%20PRINT.pdf
You should have got that, or something similar with your exceedingly expensive cranks.