I think this thread is pretty much asking the same question.
I found this quote in it:
"All 2.0/2.3/2.5 heads will physically bolt in place of each other. They all have similar exhaust port shape and placement. All cams are interchangeable as long as they are used with the proper followers. Later model (1995 and newer) roller cam followers cannot be easily swapped onto an older head as the valve stem size was reduced in the newer heads and matching slot in the follower was reduced. Early 2.0 and 2.3 heads have the same small round intake ports spaced evenly apart. They differ from each other in their valve sizes though."
The other quote mentioned having to modify the downpipe to fit an O2 sensor bung, but I'm cool with that.