The following has been edited & retyped from an article by Martin Cliffe (Omicron Engineering Ltd) published in the UK LMC Viva Lancia!Magazine, March 1993 pp. 29 to 31.

1. The camshaft timing must be set before the ignition timing can be set. Both contact breakers must be set to 0.45 mm making sure each one is fully open.
2. Bring the engine to cylinder No. 1 TDC with both its valves closed. This is when the ‘O’ mark on the flywheel is in line with the ‘1/4’ mark. This means there will be clearance between both valve tips of cylinder. 1 & their rockers. If there is no clearance & the tappets have been set correctly, then the engine is at the end of its exhaust stroke & the crankshaft will have to be turned 360º. Recheck that the rockers rock.
3. Install the distributor drive shaft so that the slot lies exactly fore & aft (in line with the longitudinal axis of the engine & car). The slot is offset, so that the distributor shaft will only fit one way round; the offset should be in the direction of the 2-4-6 bank, or in other words, the large segment should lie towards the 1-3-5 bank. There are two complications: the slot at the other end of the shaft has to engage with the oil pump, & the skew gears that drive the distributor make the shaft rotate as it slide down to mesh. Usually trial & error is required to get a correct fit & the engine may need to be turned to engage the oil pump. Slight downwards pressure on the shaft will help you feel when engagement occurs, but the engine must be brought back to the TDC position to see if the slot is still fore & aft. You may have to do this several times, moving it a tooth at a time, but patience will be rewarded.
4. Next install the distributor mount aluminium casting with its lug for the clamping screw facing front & right.
5. The distributor itself may now be fitted, ensuring the clamp is in place with its pinch bolt to the rear, close to the greaser cup. The correct position is for one of the two spring clips for holding the cap to be in line with the lug on the distributor mount & the greaser to be towards the rear left of the engine, as shown in Figure 1. Screw the M6 bolt through the clamp into the mount & tighten it so that the screw is roughly in the central part of the slot. The distributor will still turn because the pinch bolt has yet to be tightened.
6. The distributor must now be timed so that the spark occurs at the correct point, & the two contact breakers are correctly in phase so that all 6 cylinders fire at equal intervals. Proceed as follows:
7. Rig up a test light consisting of a 12 V battery & a low wattage bulb. Connect one side of the battery (say negative) to an earth on the engine, & the other, positive side of the battery to the light bulb. Complete the circuit by connecting the other terminal of the light bulb to the low-tension terminal on the distributor. Obviously the light will come on as long as one or other sets of points is closed. Turn the engine in the opposite direction to normal running (anti-clockwise) by about 30º & then forwards until the TDC mark on the flywheel lines up with the fixed ‘AA’ mark on the engine block. The reason for turning backwards & then forwards is to eliminate the backlash in the chain gear & the skew gears. Any critical movement must only be made in the running, clockwise direction, when viewed from the front of the engine. If you overshoot the TDC mark repeat the above procedure.
8. Now turn the distributor until the light comes on, then very slightly anti-clockwise until the light just goes off. Tighten the pinch bolt so the distributor is locked tight. To make sure the ignition timing is correct, turn the engine back by 30º, and then turn forwards slowly. The light should be on & go off exactly as the ‘O’ mark passes the ‘AA’ mark. If not, make a slight adjustment to the distributor position & repeat until correct. The engine is now timed for ignition on cylinders 1, 3 & 5 & you will have noticed that it was the rear contact breaker that was switching light bulb on & off. This contact breaker is fixed to the distributor plate. The other contact breaker for cylinders 2, 4 & 6 can be moved in relation to the first & it is vital to phase it correctly so that all cylinders fir at equal intervals. This phasing is also known as the dwell angle & may be set in three ways:  
9. It may be set before fitting the distributor to the engine by fixing a 360º protractor to the spindle & using the same test lamp method it will be possible to see if the light goes off every 60º of turning. The moveable contact breaker must be adjusted until this is achieved & I try to get the error to less than 1º of distributor rotation.
10. If you do not have an electronic engine analyser, the best method is to time as described in section 7 above & then turn the engine a further 330º (a full turn less 30º - obviously a further full turn of the crankshaft would bring us back to where we started, noting that all 4-stroke engines fire all the cylinders in two revolutions of the crankshaft, however many cylinders there are). With the test light connected as above, further rotation of the engine should make the light go off as the ‘O’ mark reaches the ‘AA’ mark. This time the front contact breaker will be the switch, the exhaust valve for No.1 cylinder will just be closing & the inlet just opening in the overlap phase, & the rotor will be pointing towards the contact for No.6 cylinder, marked 4 (meaning 4^th see Figure 2) on the distributor cap. If the light goes off at this point, the engine is timed & phased correctly. If the light goes off between ‘AA’ & ‘1/4’, then the moveable contact breaker should be moved anti-clockwise, & conversely, if the light goes off before ‘AA’ is reached, the moveable breaker needs turning clockwise.
11. If you have an electronic engine analyser available with an oscilloscope display you can see the primary or secondary traces above one another. Most analysers automatically align the points opening signal (start of ignition). If all the cylinders are firing equally, the points closing signals should all be directly underneath each other on the display. If they are not, as shown in Figure 3, adjustment of the moveable breaker will bring them into line. There is an advantage in doing this with the engine running as they small variations due to vibration, deflections, running clearances etc. are taken into account & you can also see if one or other cylinder is firing erratically. A worn or bent distributor will also be revealed.
12. The initial spark timing should be checked with the engine running by using a stroboscopic timing light. If all was done carefully there should be no more adjustments required!