Many commented on the wind blasts at Houston and Elm. No one standing on the street said they felt an anything like bullet shock wave or muzzle blast. . Also, the Kilduff car was not a convertible. It was the National press-pool car, a grey/blue two-door 1960 Chevrolet Bel Air sedan hardtop.
I can understand that what you and Royell are saying about Kilduff not feeling the repercussion so much as hearing it, that seems reasonable because of his car, but Kilduff was pretty insistent about the loudness and direction of the shots on his right ear. And as you mention Weigman, saying he also felt it, was in his open car and got out after the third shot.
As far as feeling a shock wave, I’m in agreement with you, I’m skeptical that anyone, anywhere in the entire plaza would feel the shock waves.