YES like night and day.
YES they are different. They will NOT INTERCHANGE.
Pass side valve cover.
take off the valve covers, and the rocker arms will have adjusting nuts on them, tighten them to zero lash and the back off 1/4 turn.
On my retrofitted to R134-A the fill valve is underneath the airbox. You have to take it out to get to it.
On the right side valve cover.
yes it does, all engines have a pcv valve ( positive crankcase ventilation ) valve. it is on the engine and vacuum goes to it from the valve covers.
YOU can't. It don't have 1
The idle air control valve is located on the throttle body, and the EGR valve is located on the intake manifold.
It is very easy to access in the left hand valve cover near the oil fill opening. This is the valve cover closer to the radiator. If you pull it up, it will slide out.
Check for vacuum leak or faulty EGR valve.
From what I've been told Chevy's do not have fuel shut off devices.
It should be attached to the base of the throttle body.