Coil Confusion

The orange box on the car was installed by the PO.
This is my son's car and he's not a "hot rodder". I'm OK with switching to a square, e core coil and stock ignition box or stock coil (purchased last night).
so, since this is basically a daily driver, can I downgrade from the orange?
Is it as easy as swapping the ECU and coil? What color ECU should I get?
Additional info: Edelbrock performer intake with Edelbrock 1406 carb. Mild Cam, specs unknown.

Thanks