Cameron,
If accuracy is paramount to you, be careful of the reference sources you select. The photo you provide is most likely a Superformance MK III replica, not a CSX 4000 as labeled. The forward-on-top radiator, sharp nose lip and a non-original hood scoop suggest that. Many Cobras posted on line are replicas and the posters don't know that.
The magnesium Halibrands shown by JC are nicely done. However their 1:1 dimensions are 7 1/2" F, 9.5" R. They have different backspacing.
Aluminum replicas made by Trigo and Vintage Wheel are dimensionally correct, but you can spot them because the valve stem is in the web, not the rim face as Halibrands. Real Halibrands and Trigo replicas are 6 pin drive, Vintage's are 5 pin with bolt on adapter.
GT-40 wheels are noticeably different than Cobra II's in the web area.