NOTE:
Identify each part as it is removed so that each item can be reinstalled in its original location.
Inspect the rocker arm shaft and the rocker arms.
If reused, the rocker arms must be installed in the their original locations.
Remove the rocker shaft bolt before removing the rocker shaft from the rocker shaft holder bridge.
Prior to reassembling, clean all the parts in solvent, dry them, and apply new engine oil to any contact points, the bearing surfaces, and lost motions.
When replacing the rocker arm assembly, remove the fastening hardware from the new rocker arm assembly.

System Controls
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Brake Booster Replacement
Remove the air cleaner cover and the air cleaner case.
Remove the master cylinder.
Disconnect the brake booster vacuum hose (A) from the brake booster.
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Rocker Arm and Shaft Inspection
Remove the rocker arm assembly.
Disassemble the rocker arm assembly.
Measure the diameter of the shaft at the first rocker location.
Zero the gaug ...