Factory EFI A body conversion

Yes. All of the sensors used to run the engine properly are needed. Going by memory, that includes MAP, TPS, IAT, ECT, O2, cam synch (the factory EFI distributor), and crankshaft position sensor.
Outputs needed are the IAC and injectors.
Fuel pump relay can be controlled by PCM or separately from a wired ignition source if preferred.
I'm sure I forgot something there, but it's most of the main items for a factory Magnum setup to run properly. Same stuff used on aftermarket systems that do not use throttle-by-wire or mass air flow metering.