Make, model and year of vehicle and the engine option would be nice.
Drivers side, front plug.
Goes to driver's side bank at very front-follow the wire
The number #1 plug is the forward-most plug on the left (driver's) side. Trace that wire back to the cap and you've got your answer.
The distributor cap should have the number 1 marked on it. The distributor cap is installed with the # 1 position facing the engine , slightly towards the drivers side of the engine
With hood open, standing on the passenger side, #1 on the distributor cap would be at the 10 O'clock position.
Most good quality caps have #1 labeled in a raised number.
Click the link.
1 left side back(long wire),2 left side front(short wire), 3 right side front(short wire),4right side back(long wire)
number one wire will point to the number one cylinder
Left and right are determined by sitting in the car, facing forward. On a Chevy 350, number 1 is on the left or driver's side (in the USA) furthest forward cylinder. And you don't put the plug wire anywhere on the cap. You must bring number 1 cylinder up to top dead center on the compression stroke then lift the distributor cap and see which tower the rotor is pointing to....that will be number 1 tower. look at your cylinders the left side is 2,4,6,8 and the right side is 1, 3, 5, 7 and the whole firing order is 1 8 4 3 6 5 7 2 so you put one spark plug wire on lead it to the number 1 cylinder then put the other end anywhere on the cap then get another wire put it on the 8 cylinder put it right beside your first wire but clockwise then you repeat the steps until your done then fire it up! if you have any questions about engines ask me - moparman48
..** * ...* * ...* < Number 1 wire goes here. ..** /\ Front of distributor cap.
A good quality cap will have a #1 mark on it. #1 cylinder is front driver side.