I'm in the middle of putting a '97 2.5 into a 2001 base, sort of the opposite swap. In my case, I swapped over all of the 2.7L intake, fuel, harness, and vacuum stuff to the 2.5. The only real creativity involved was making a template and re-drilling some of the mounting holes in the intake a few mm over from where they were.
There's a big difference in the 2.7L intake and the 2.5L intake. By my HF calipers the intake port on the 2.7L engine is 54mm vs 43mm on the 2.5L. Between that and the resonance tube, I'd want to keep the 2.7L intact and look at swapping the DME and adding some wiring and pedal for e-gas.
Easiest way to do it and be back on the track would be a direct swap of all the intake, throttle, engine harness, vacuum, and injector stuff from the 2.5 onto the 2.7 - the reverse of what I did. To re-drill the intake mount, just make a template, knock out the steel spacers, (fill the old holes if you want quality) and drill holes in the replacement intake.