There are several aftermarket computer controlled fuel injection systems on the market. Accel, Holley, Edelbrock, and Motorvation all make such systems. But none of these systems will control the transmission shifting; which I believe is computer controlled on your vehicle. And they probably also will not interface with digital dashboard displays. In addition, they are not legal for use in emission controlled vehicles which were originally equipped with fuel injection, and which are operated on public roads. So your car would not be able to pass a smog test; and you would be potentially subject to a fine, if the modifications were discovered. That does not sound like a simple, or a clean solution.
In reality, these systems are just designed to convert older carbureted engines to fuel injection. They are not intended to replace factory purpose built engine control systems. And they are largely engineered for Chevy V-8s. Edelbrock has systems for Chevy, Ford, Chrysler and AMC; but their Ford systems are only made for 289, 302, and 351 engines. Holley makes universal throttle body and multi point injection systems; but they both have a 4 barrel throttle body, that mates with a square flange, single plane 4 barrel intake manifold normally used on carbureted engines. They also make a 2 barrel TBI system, but it is limited to motors with less than 275HP. So nothing that is currently available is made to fit the Lincoln 4.6 DOHC engine. In addition, the 4.6 DOHC engine is known for its great fuel economy. If you were to retrofit one of these universal systems to that engine; I'm sure you would not be able to get anywhere near the fuel economy of a stock system.
I hope this helps!!!