Take out spark plug #1 (left of engine, nearest timing belt) and turn it over by hand till cylinder #1 is at the top of its travel. Then remove the dizzy cap and check where the rotor arm is pointing, the rotor arm should be pointing at a notch in the dizzy, which should correspond to spark plug lead #1. If not the intermediate shaft has moved, its free to spin when the belt is removed.
You can either loosen the timing belt and adjust the intermediate shaft sproket, twist the dizzy till the rotor arm lines up with the notch, or you can move the spark plug wires round so that the arm is pointing to the lead which runs to cylinder #1, then fit the rest of the leads in sequence 1342 clockwise
