How do you replace bad lifter in 351 Windsor?

To replace a bad lifter in a 351 Windsor engine, you'll first need to remove the intake manifold and valve covers to access the lifters. Then, if necessary, remove the pushrods and rocker arms to reach the affected lifter. Carefully pull out the bad lifter using a magnet or a lifter removal tool, and then install the new lifter in its place. Reassemble the components, ensuring everything is torqued to the manufacturer's specifications, and check for proper operation before starting the engine.