ThanksDon't have the answer to your question. Sorry.
However, removing the air pump is illegal and in states with annual inspections, (like New York), by law the vehicle can't pass inspection either. Brooklyn N.Y., if I recall correctly, also has enhanced emissions inspections a vehicle must pass and that too will cause it to fail inspection.
We all need clean air to breathe and live.
Cool ill check that out.AIR Pump TSB
EPA approval for disabling the AIR pump on your vehicle.
This does not technically allow for removal but............................. apparently even the EPA doesn't believe the AIR system on this car necessary for us to have clean air to breath.
You may want to take back that "thanks" now
Far as the 4.3l thing get a mirror and look behind the driver's side head it will say 4.3 or 5.7
core support could have been changed.