this seems too good to be true but a friend of mine is selling me his fairlane 5.0, not sure what model but its a 1992, at a very very good price. now my question is would it be possible to put that engine into my ef fairmont. I will have the whole car so i have every part necessary (i think) will there be any ECU problems or would i have to use the older ECU? will i need to swap the auto transmission as well? also will there be any legal problems as i'm fitting an older model engine? any help is much appreciated.

It wont be a straight swap as you will need to source the wiring loom and possibly the ECU from an EF V8. The Auto will have to come too, there should be no difference in the engine. You will need to retain your tailshaft as the LWB is longer. I am not sure if the EF V8 ECU controls the Auto or not so there may be complications here as well.. Radiator and hoses will need to be checked for a match as well.