Intake manifold will have to change. You can swap all the attached necessaries and accessories over to your donor engine. Some will be easy (alternator, AC, Power steering); and some maybe not so much (EGR valve comes to mind). Try to find a donor engine that most matches your current engine. Does it have an EGR? Are there emissions lines run near the power steering pump? Where do the water temp and water sending units connect? (this is important, as you'll want to keep your current engine harness/ECU combo.
Having said all that, these engines are like !ego blocks, with some minor annoyances. I've put 2.2 SOHC single port engines in cars that had DOHC 2.5s, and just put a '09 2.5 in my wife's '99. Still don't have the AVLS hooked up yet.
Good luck, take your time, do your homework. YMMV, not my fault.
-runnamukk in MD
PS - where are you? I have a moderate buttload of intakes/heads/engines if you're in Maryland.