1990 Corvette Engine Knock

I have a 1990 corvette with 60,000 miles & a L98 engine. There is a knock in the bottom end of the motor when the clutch is out. When the car is in neutral the knock is even louder. I was told that when the clutch goes in & out it pushes on the crank shaft, so I'm told that a bearing is going causing an alignment problem with the crank shaft. It seems I need a bearing replacement. My questions are: Does the engine have to come out of the car? Is there a kit available? Is this a common problem with this year vette? Any information would be greatly appreciated. Thank you, Chuck