replace rod bearing

I just bought a 97 Achieva with 2.4 twin cam motor, and it has a bad knock, sounds like a bad rod bearing. I haven't got a manual for it yet, is it possible to fix without pulling the motor?

I know of other people who have dropped the oil pan on a 2.3 quad to replace the oil pump while the engine was still in the car, you could probably replace a bearing that way, would be a pretty messy job I imagine though with all the oil still dripping from the engine.