A PO replaced the points system with a Petronix ignitor system on my 1971 4.2 litre and I have never been entirely happy with it. The distributor seems to be in the wrong orientation - the vacuum capsule pointing obliquely towards the block where it fouls the heater pipework when turned to the correct ignition timing position. I suspect fitting the ignitor pick up and magnetic cam sleeve has somehow altered the point at which the spark occurs necessitating rotation of the distributor to its present orientation to compensate.
I have tried moving all the HT lead connections round one hole and turning the distributor to compensate (60 degrees) but that is too far and the dizzy then fouls the water pump connections. What I really need to do is turn the distributor to advance by about 20 degrees whilst retaining the original timing set up. I can do this by moving the drive by one or two teeth but that means taking off the sump……….
If I re-drill and re-position the pick up base plate to retard by 20 degrees and then rotate the dizzy to compensate by advancing 20 degrees I am back where I started and have not changed the timing but will have a better orientation for the vacuum capsule. However, the position of the HT terminal contacts will have changed relative to the spark.