As I recall with the Blue Angels anyway, the guy riding in the backseat to and from the showsites wasn't a pilot. He was the enlisted crew chief for that particular aircraft. I'm assuming (a dangerous thing, I know) since the rank of the individual whose name is painted under the rear canopy is 'Sergeant', that it was likely the same situation with the 'T-Birds.
However you ultimately choose to go with it - with one occupant or two - it's going to turn out great. I love showbirds, but generally tend to shy away from modelling them. It's so much easier to fix a screw-up on a "plain-jane" bird. But you clearly have a knack for it. I'm envious!