You can keep the 351C distributor if you want to. But you can also put in a High Energy Ignition (HEI). The distributor from a 460 (big block) drops right in. Find your basic Lincoln Continental in the junk yard. Look for the distributor that has the Dura-Spark II. The others are not as good (I don't know exactly why). Get one with a vacuum advance. These are in the 1975 to 1979 engines. I got mine from a 1976 Lincoln Towncar.

Years ago, there was a "Ford V8 Workshop" website. Bill had a lot of information there about this interchange. He took down the site. Some of these are Bill's pictures, others I got out of a Chilton's Manual. Bill, if you don't want me to use your pics, email me. I will get my own, otherwise, thanks Bill!

Basically, you need to get the distributor, the distributor cap, the coil, stator and the module itself. Here are some pics.

 

Distributor: Note the vacuum advance unit attached	Cap: The cap has a goofy tapered plastic ring and a cap. This is so the diameter of the distributor could stay small (unchanged distributor) but get the addidional plug contact spacing required. The HEI spark will jump across terminals if you try to use a small diameter cap.
Coil: The coil looks a lot like the standard coil, but it isn't. If you try to use a standard coil you simply won't get the spark you are looking for.	Module: There are several out there. The "correct" one has a light blue label, as shown in the pic. Get all the harnesses that come with these. Don't cut the wires and hope to make new connections.
Wiring Diagram:
Stator and wires: Not much to say about these.

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