It is the driver side rear cylinder.
Front driver side.
Chevrolet 350 or Dodge Hemi it is driver side front.
passenger side third spark plug back Driver side ?
#7 spark plug is the last plug on the left side...that is the drivers side of the truck
On the four cylinder engine the number one spark plug is the first spark plug on the left side looking over the radiator. On the V6 the number one plug is the first spark plug on the firewall side of the engine looking over the right front fender.
It will be the last spark plug on the rear of the passenger side of the engine.
The number on spark plug is the one closest to the front of the engine. (The front is the side with the belts.)
Number 3 is passanfer side 3rd one back, number 4 is first one on the drivers side
Drivers side, first spark plug in front is #1
front driver side
Number one is driver side front.
It is the one closest to the radiator on the passenger side