Silverado Classic 1500 2WD V6-4.3L (2007)
6. Disconnect the power brake booster vacuum hose from the vacuum fitting.
7. Remove the positive crankcase ventilation (PCV) valve hose from the valve cover and rocker cover.
8. Remove the rocker arm cover bolts.
9. Remove and discard the rocker arm cover bolt grommets, if necessary.
10. Remove the rocker arm cover.