Intake manifold on the AMC 360 needs the heat shield. Might have to take the one off the old intake.
Valve train is another obvious difference.
Some stuff that is not AMC:
The ignitionsystem is Motorcraft. Alternator is Delco - should be 12SI. Starter for '91 may be Chrysler. If not its Ford.
The starter may still have a remote 'ford type' solenoid, but by '91 there also is a Chrysler type starter relay.
Transmission is Torqueflite 727.