Curious on how GMC V6 owners change their flywheels and still keep their rotating mass balanced? I have had my 351 V6's in the engine rebuilders shop in the years pass and they always required the flywheel to be mounted at the time of rebuild /balance - they are different flywheels for the Powerglide and Turbo Hydramatic as well as the clutch flywheel. I'm planning on changing my Powerglide to the 3 speed Turbo 400. Whats your thoughts?