EFI Swap on '66 289

First off I'm going to say this because no one else has. Use the search button.

Second, for all intensive purposes a 5.0 is a 302. There are minor differences between them but they are the same basic engine block.

Third (personal bias), stay the hell away from Mustangs Plus.

Fourth, if you have all of the proper components from a 5.0 motor then yes, you can just bolt the upper and lower intake onto your small block 289/302. Keep in mind that you are going to have to do other things such as add a return line to your fuel system and install an EFI electric fuel pump. You are going to need a lot of parts that you wont get just from buying an engine. Stuff like the ECU, O2 sensors (must modify your exhaust to put these in), wiring harness, fuel pump inertia switch, other EFI sensors. If you are lucky, when you buy an engine, you will get a lot of that stuff along with the ECU and harness. This is not a simple switch of the intake manifold and you are running an EFI motor swap. You have to install all the stuff that goes along with supporting an EFI system.

A good place to start the learning is http://fordfuelinjection.com/

Basically, read everything on that website and then come back here if you still have any questions.

My advice if you are going to do this swap, especially if you want a T5 with it.... try to find yourself a donor car. The condition of the motor is not especially important because you can always bolt the manifold to your car's motor. Try and get one that will run so you can drive it back home and then gut it for everything you need. After that donate it. This is one of the best ways to do this engine swap because the donor car has all the stuff you need.