This is the correct 55 Amp alternator with the D1ZF-10300-AA part number used on 71 429 CJ/SCJ.

Rear view of the 55 Amp alternator.

From the factory, a red highlight was placed over the part number as shown in this picture.

This is the 3.05" diameter D1Z stamped steel alternator pulley used on the 429 CJ/SCJ Mustang.
 

Note that both the Pulley and Fan were both Yellow Dichromate coated as shown in the sample above from a 428 CJ.

The Alternator Pulley was marked with;

Service part number D1ZZ-10944-A and stamped Engineering part number D1ZF-10A352-A1A  

   Machined -vs- Stamped Steel?

We have found two different versions of these pulleys - one in stamped steel and one machined. The best we can tell, it appears that the original factory pulleys were the stamped steel and some of the service pulleys were machined.

Voltage Regulator and installed view

AMK Products - Below photos are of AMK's reproduction 429 Alternator and Voltage Regulator

Alternator Wiring - this photo shows at proper attachment of the wire harness to the alternator.

Alternator Splash Shield     

This is an ultra-rare 429 Mustang Alternator Splash Shield. It was made of a sheet of rubberized material and was held in place by fasteners which mounted into the side of the passenger frame rail. A sample of the grommet used to attach the shield to the frame is shown below;

Template to Make Your Own Alternator Splash Shield

Group member John McMasters has kindly provided a template based on his original shield for those who want to make their own. Click the link below to download the pdf format template:

Alternator Splash Shield Template

Note: To open the template file, you must have Adobe Reader downloaded on your computer. For your convenience, here is a link to the Adobe website where the Reader download is located:

Adobe Reader
 

Battery

For 1971, Ford offered both a Group 24 and a 27 battery, but the 429 Mustang/Cougar used only the 27F. A correct Autolite Group 27F Battery is shown above, as well as an installed view. The battery tray, hold down, and fender bracket are also shown above. For those wishing to buy the Autolite 24F Battery cover that fits over the top of a standard battery, here are the dimensions of the battery you will need and the post hole locations for the cover to fit;