Well if you go with a 00+ motor you have to tune it some how, and if your running the 97 ecm then youll have to buy hptuners anyways since you can use the GM flash, not to mention you have to convert to the right injectors and make the knock sensor fit on the 00+ motor. But if you want to use the 00+ ecm for the GM reflash you have to buy a new ECM and BCM plus a new cluster and so on and find a vin for a 00+ car to even get the reflash. So ether way, your going to spend more then just what the charger cost.