There has been some confusion on the proper way to install a Pertronix Ignitor on a vintage Mustang. The instructions that come with the unit are clear, but are also "generalized" for use with all makes of cars. There are several quite misleading statements on the instruction such as "If your ignition system presently has a ballast resistor, do not remove it". Of course this is actually true, but what they mean is that the coil still needs the resistor. The Pertronix will not run properly when connected to a coil with a ballast resistor in the circuit, it needs 12 volts. The statement that straightens this all out is, "The red wire from the Ignitor must be connected to the positive side of the coil or a 12 volt switching power ." As far as a Ford is concerned, that means a 12 volt switching power source. There are many other makes of cars that use a 12 volt feed straight to the 12 volt coil, not Ford....we use a 6 volt coil with a resistor wire between the coil and the ignition switch.
What this means to us is that we need a place to connect the red wire to get a full 12 volts. On an early Mustang the choices are limited. The heater positive wire and the voltage regulator both have switched 12 volt sources, but neither is sutable because of other reasons on most cars. The proper way to get power is to run a new wire from the green/red wire where it connects to the back of the ignition switch. This green/red wire is the wire that turns into the pink resistor wire and runs to the coil + side. You must leave that wire connected so the coil will still have power and just connect the new power source wire where it connects at the back of the ignition switch. There must be a dozen "proper" ways to make this connection so I will leave that up to you, but they must BOTH be connected to the IGN terminal.
The instructions say to use 20 gauge wire.... I would use 18 gauge or better. Route it how you wish, but a clean way is to run it along the same "engine harness" that the stock coil, temp sender, oil press wires are in, you can re-tape it and it will dissapear. This runs from a gromet just behind the engine on the firewall and is a good place to run it through. (just a tip.....push it through from the engine side and then find it under the dash. Trying to go from the inside of the car is difficult if not impossible). Tie it up well under the dash because if you catch it with your toe on a quick shift on a Saturday night........well, you know.
Just cut the loop connector off of the red wire from the Pertronix and connect the two with a male and female spade connector and this part is done. The black wire from the Pertronix just goes to the - (points) side of the coil. Make sure there are no condensers on this side of the coil, if so remove them.
I'm not going to go into how to mount the unit itself. The instructions are fairly clear......It's just like replacing a set of points. (P.S - remove the condenser inside of the distributor!)
These things are great! I have to say this is the best upgrade anybody can make to their classic Mustang or Ford. No more replacing points or condensers, or associated problems with bad dwell or timing. No slipped points or bad condensers at 3 in the morning on the way to that next Mustang show!
I've included diagrams for the other possible configurations on a modified car. Happy cruzin'......, whisperer.