Found it
From" Shelby Cobra Gold portfolio" ( picture of about 30 unfinished competition cobras out in an airport lot)
When it was realized that the required 100 427 cars wouldnt be built in time for the FIA inspection ,AC was sent word to begin building street cars. The race cars sat behind Shelby American to be completed as they were sold. When it was realized that the market for 427 competion Cobras was glutted the cars were offered as s/c 's the " street competition " model.
As standard equipment it came with ; rear fender flares,
oil cooler scoop,side exhaust competition, fuel filler, roll bar,hood scoop,brake scoops,
oil cooler ,quick jacks, [ 427 medium riser,with dual 4 bbl carbs ] ( although some had single 4 bbl carb) also battery mounted behind passenger seat ,a differential cooler,a 42 gallon gas tank, front sway bar, and 3.77:1 rear gears
I also think the range of extra horses from the 2x4 is 25 to 40
Karl