28 or a 50oz? (FWIW this IS and EFI truck)

 

Flywheels are generally separated by diameter, not weight. You will have a 9,10, or 11" flyweel, depending on which tranny is behind it. 28 or 56oz doesn't make any sense. even 56oz is only 3.5 pounds. Even a 9" flywheel is going to weigh about 45 pounds.

Sidewinder

 

the flywheels have an imbalance to them that matches the harmonic balancer which is either 28 or 50 OZs

 

LOL I too live in Mechanicsvill VA