Typical regression for lap time over the years (due to evolution of tires, suspension, brakes, gearbox, electronic controls, etc) and the regression for power and weight would suggest a lap time around 1\'07 or 1\'08 for the Cobra 427 - with tires as built in 1966.
2010 tires of the same dimension bring say 2 to 3%, so we could expect about 1\'05 to 1\'07 for this test - obviously with a lot of uncertainty.
Now the engine could possibly deliver something >450 hp, meaning 1\'04 to 1\'06.
The 1\'04.5 are therefore strong but not unrealistic with new tires and a well prepared engine.