Need Ecm Selection Help

I am looking at buying a '75 Granada and 4.6L with auto trans and need some help identifying which ECM is compatible with the engine. The guy is claiming it's out of a '95 Lincoln Town Car but does not have the ECM for it. I am wanting to use a Mustang ECM in hopes of getting better performance out of it. I can get engine and trans numbers if that would help.

I want to drop in the 4.6L in place of the 250 I6 that the car currently has because I believe I will get better performance and gas mileage along with pass emissions easier.

Any suggestions or advice will be greatly appreciated.

Ok. I have experience with older Hondas, like late '80s, early '90s, and I know you could switch ECMs fairly easily by adding or removing a couple wires to the harness whenever you swapped from one motor to another, but wasn't sure on Ford products because I haven't worked on them.

I didn't even consider or think about a stand alone unit and actually think that will be my best bet since I am putting it into a classic. I do plan on keeping the '95 fuel injection and ignition system for now, but have plans to upgrade once I work out the kinks in the engine swap.

Any good stand alone units that you could suggest? Any thing else I should consider or think about for the electronic control systems on the 4.6L?

I am a mechanic, but this is a whole new ball game for me with doing this build. I know I'm gonna like the challenge though and hopefully the end results.