Richard - Thanks for the info; however, as noted in my Reply # 11 of last night (early this morning), I sent my original off and had it professionally reproduced, exactly like my original.
Marty - Thanks for the pictures. My plug connector is exactly like yours, including correct color and positioning of the wires. However, the harness on the rear of the Alternator does look different. As you noted, it is hard to get a good picture of the harness on the car; but, it appears to me that I only see one rubber boot (possibly a faded red one ?). In addition, it looks like some kind of rectangular "block" at the top ? Also, is there a separate wire from your Alternator to the Starter Solenoid ? Is this on a "non tach" car ?
Your picture now adds something else that I should have included in my original "list of questions"; since, as of January 1967, there were 3 Alternators (38, 42 and 55 Amp),shown as "correct" for 1967 289 Mustangs, did all use the same harness ? Another possible variable.
Finally, since yours and John's cars were built at the same Plant, and only a couple weeks apart, assuming that they had the same Alternator, and that there is no difference between a Convertible and Fastback Harness (at least no written evidence that I have seen), wouldn't it make sense that the harnesses should be the same ?
Bob