Cobras by nature and design will never be "safe" cars and efforts to engineer safety in and to festoon them with multiple bars, pads and bulky bodies with extra long wheelbases might work, but eventually you end up with something other than a Cobra - sort of like bolting training wheels, bumpers onto a motorcycle.
At that point, one might begin to question whether they wanted a Cobra at all, or just some car with cool bulging fenders, sidepipes and a big opening in the front.
Having said that, a roll bar pad like the one you're designing looks good and makes sense from a practical point of view and I also like the SPF seats with the discreet, removable, period-looking headrests. Far nicer than the incongruity of cramming in a pair of huge, modern high back seats.
