Early Shifting Question

[project82GT]

Hey everybody, i recently bought a 92 gt mustang w/ aod trans. This is my first automatic mustang, and when ever im full throttle accellerating it shifts at 4400 rpms. My other mustangs were manual and i would wrap them out to 5500 - 5800 rpm before i shifted. I was wondering how to get the auto to shift later, maybe a shift kit? ecu swap or re-flash? any feed back is greatly appriciated. thanks!