That could be hit or miss. Not all screens attach in the same place or way, and the bikes could be identical in some aspects but different in others. So while one screen may work on both bikes, another screen might only work on one of them. It would be best to lookup that exact screen or one from the same manufacturer with the same mounting.Go to Bike Bandit and look up a stock windshield for an '04 Aero, then look up the same for an '02 Spirit.....see if the item numbers match.
I've done that for a few items on my Spirit and VStar and it worked out ok.