I'd recommend a stock one. They originally came with single points, dual points and if you are a fiddler, can be converted to electronic with various drop-in modules, or even, with a little junkyard work, full Ford factory electronic as the 429-460 Ford truck engine uses an identical unit that will drop in (check the drive gear though- may need to use your original one). Many (but not all) aftermarket distributors use a bronze drive gear intended for racing, and which wears rapidly. Others have no vacuum advance which will affect your gas mileage.