Im pretty sure that this setup is possible.........but there are two ways to do it. The thermo fans should drop straight into the fittings on EB/ED radiator, the only problem is the controlling of them. The EF-> fans use a series/parallel type setup through relays which are controlled by ecu. The only (proper) way I can see of doing it is by using computer and loom from EFv8 or similar.
The easy way out (so to speak) would be to use the old thermostat type setup which has a thermostat probe mounted in the top radiator hose. This thermostat is adjustable and turns relay on/off at desired temperature etc. Make sure to use relay and to wire up to A/C as well. (i can give you more details / diagram if required). I have heard of a temp sensor that actually screws into engine that has a seperate adjustable module. I think it is made by davies-craig. This would be a bit neater & reliable than the probe.
The drawback of this setup is that both fans would come on flat out together once the engine got to desired temp, whereas ECU setup would turn on low fans when engine running, and kick in to flat out when required.
Thinking of doing this conversion to my eb v8 one day, so I'll let u's know.(thats if FF still exists by then)
ECU should be the same plug.....but i reckon that youd have to change the loom cos the extra relay wiring (3 or 4 relays depending on model) is not catered for in the motors running the manual fan system.
From following various EEC mailing lists I can say that the EEC-IV have the necessary smarts to handle the swithing of relays for thermo fans, *but* not all EECs have proven to be successful in this. Pin 41 on the EEC-IV controls this function and there are settings in the ECU to set the temperatures for fan turn on/off which can be changed if you have a service port plug in type chip/tuner.
For more information check out the mailing list at yahoogroups and this page:
One thing to be aware of is that the original radiators for pre ED falcons (Clutch fan models) don't have the mounting tabs molded onto the radiator - replacement rads do though. The radiators are interchangeable however (exact same boltup etc) From experience the Davies Craig probes are quite reliable, and easy to instal / adjust (just make sure you get a good seal where is goes into the hose)