You will need the distributor, cap, rotor, and ignition module from a Capri II 2.8, and a couple of solderless wire splicers. If you are using a 1977 distributor cap you will also need a set of plug wires. The wiring harness that connects the distributor to the module is helpful but not essential. If you don't have the harness, you will also need a set of 2 pin and 2 sets of 4 pin Molex latching connectors (available at Radio Shack), some 18 gauge or heavier wire, and a flexible plastic wiring holder (available at many auto parts stores). A wiring diagram for your car is also a big help, and a new ignition coil would not be a bad idea.
The "high energy" ignition system used on 1977 and later models is preferable, though the earlier one will also work well. One possible problem with the "high energy" system is that the distributor cap is considerably larger; it may interfere with some air cleaners, particularly aftermarket air cleaners used with the popular Holley 390 CFM 4-V carburetor. If you need extra clearance, the 1976 cap will fit the 1977 distributor. Dave opted to use the 1977 cap, and instead put a thick rubber gasket between the Holley 4-V and the air cleaner to get the necessary clearance. Also, if you can't find a "donor" 1976-77 Capri II 2.8, look for a 1976 or later Mustang II, Pinto, Bobcat, or Ranger fitted with a 2.8 V6.
The first step in the conversion is to remove the distributor cap. Rotate the engine by hand until the timing mark on the crank damper indicates 0 degrees (TDC), and the rotor points towards the #1 plug wire (or where it would be). Note the orientation of the rotor.
Remove the distributor hold-down bolt, disconnect the wiring and vacuum hose, and remove the distributor. Replace it with the electronic ignition distributor. Be sure to install the new distributor so that the rotor points towards the #1 plug wire, in the same orientation as it was on the old distributor. Install the distributor hold down bolt. Connect the vacuum hose.
Mount the ignition module to the inner fender. You will find that Mr. Ford thoughtfully provided a shallow recess on the left inner fender that's exactly the correct size. Drill 3 mounting holes in the inner fender, and put some primer on the exposed metal to prevent rust; when it's dry mount the module with sheet metal screws as on the Capri II.
Connect the ignition module and distributor as shown in this Wiring Diagram. Note that the diagram is for a 1974 Capri 2800. The 1973 Capri 2600 is very similar. The existing wiring on the 1972 Capri is a bit different, so the wire colors and connector numbers will not match the diagram. Also, the 1972 tachometer is current triggered rather than voltage triggered like the later ones, it won't work with the conversion and should be disconnected. It is possible to make an adaptor for the 1972 tachometer; e-mail Larry if you're interested in using the 1972 tach with this conversion, and I'll see about designing an adaptor.
The wire splicers may be used to connect the module's white wire to the black wire leading to the automatic transmission relay, and the module's red wire to the black/yellow wire leading to the resistance wire. We happened to have a spare 2 pin connector that mated with the module's connector; if you don't have one of these, replace the connector on the module with a 2 pin Molex connector.
You should not need a splicer for the module's green wire, since it can be connected directly to the ignition coil. The module's other wires go to the distributor, which is easy if you have the Capri II wiring harness; Dave and I didn't, so we made one using the Molex connectors, wire, and flexible wire holder. We cut the connector off the distributor and replaced it with a 4 pin Molex connector to mate with our harness.
Disconnect the black/yellow wire at the starter relay that leads to the gray resistance wire. This wire was used to bypass the resistance wire during starting, which isn't required with the electronic ignition.
When everything is wired up, put the cap on the distributor and hook up the coil and plug wires. If everything is correct, the car should start. Adjust the ignition timing to spec (use 10-12 degrees BTDC with the vacuum advance disconnected if you can't find a spec). You will probably find that it's advantageous to increase your plug gap to take advantage of the electronic system's higher voltage.
What can you expect from the conversion? On Dave's Capri, drivability was greatly improved, especially when the engine was cold. Fuel economy was also slightly improved.
If you have any comments or questions, e-mail Larry.