Standing in front of the vehicle with the hood open, looking at the distributor, number 1 on the cap would be at the 7 o'clock position.
FACING THE DISTRIBUTOR WITH THE LITTLE DOOR TOWARD YOU, NUMBER ONE IS THE FIRST TERMINAL TO THE LEFT. THE FIRING ORDER IS 18436572 GOING IN A CLOCKWISE DIRECTION
The number 1 cylinder is located at the front left of the engine block while FACING the engine. Follow the spark plug wire to the distributor a POW there it is.
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
On the 305 engine the number one plug position is the first one on the right side while you are facing the engine.
The engine number is on the engine block below the distributor.
What car, what year, what engine?
Hopefully, you set number one piston at Top Dead Center (TDC) and made marks on the distributor in relation to its location on the engine, or at least remember the direction in which the rotor was pointing. If you didn't, then the first thing to do is set TDC and then stab the distributor. At TDC, the rotor points to the number one spark plug wire post, follow the firing order from there. While stabbing, you may have to rotate the distributor left or right a little to get the splines to mesh.
Hopefully, you set number one piston at Top Dead Center (TDC) and made marks on the distributor in relation to its location on the engine, or at least remember the direction in which the rotor was pointing. If you didn't, then the first thing to do is set TDC and then stab the distributor. At TDC, the rotor points to the number one spark plug wire post, follow the firing order from there. While stabbing, you may have to rotate the distributor left or right a little to get the splines to mesh.
Engine number is underneath the distributor on front housing on the rough casting. If that fails check underneath the alternator on front housing.
You need to manually rotate the engine and set the number one cylinder at Top Dead Center (TDC) before re-insalling the distributor. Hopefully, you made a mark on the distributor that relates its position to the engine in orde to re-install it as it was. If you forgot to make a mark, try to remember in which direction the rotor was pointing before you removed the distributor (assuming the engine was at TDC) and re-install it as close as you can. At TDC, the rotor normally points toward the number one spark plug wire post. Follow the firing order sequence from there.
Yes the rotor should be pointing to the #1 cylinder when you are installing the distributor.
Need to know what engine it has.