C 2500 3/4 Ton Pickup 2WD V8-379 6.2L DSL VIN J FI (1984)
Loosen and remove vacuum pump belt.
Remove vacuum pump pulley to hub attaching bolts, Fig. 3.
Remove pump and bracket from engine.
Remove bracket from pump. Hub must be pressed off vacuum pump and used on replacement unit.
Install bracket on pump.
Install pump and bracket on engine.
Install vacuum pump pulley and attaching bolts to hub.
Install vacuum pump belt and adjust belt to correct tension.
Connect vacuum hose to pump.
Connect battery ground cable.