Swapping BCMs would require replacing all the computers in the car, including all the wiring. It can be done, but it would be a lot of work, plus you MUST make sure that all the modules come from the same car so that they all have the same VIN programmed, otherwise it will shut down the car. I am planning on doing this myself, but I am waiting for my yard to get a good donor in to take everything I need.
Using a piggyback to run just the EVIC may or may not work, I know a couple members have done that for their steering wheel controls, but I'm not sure if anyone has done it for the EVIC. It's a possibility.
But to answer your question of year, you might as well do an 02+ if you're going to do it, then you could use ALL the features, including some of the newer ones.