[CompClassics]

As far as FIA 289 Cobra roadsters go:

2259 & 226O both had formed sheet metal scoops riveted to the body work. The shape of the scoop sheet metal was more angular.

The other FIA and late USRRC roadsters had formed scoops that were formed by the crew of the individual car as Dan has stated above. Most of the scoops were formed by cutting and splitting the bodywork and shaping the existing metal till it was as desired by the individual performing the modification, hence they are all a little different.

Both the early riveted on scoop and the later formed scoops had a thin leading edge appearance, nothing like the shaped scoops found on 427 cars.