I have a 1968 Mustang with a straight 6. From all the research that I could do, the engine appears to be correct for the car.
I replaced the starter with one from AutoZone - DuraLast. The starter engages fine - no noise and the car starts fine. The noise comes when the starter disengages. The noise only last a few seconds. Sometimes it is very loud other times it is very brief.
I did a compare of the old starter to the new starter and noticed that the gear in the old starter sites further back in the starter housing then the new starter. Not sure if that is the issue. I have tried to do some searches to get some views of the starter but no luck.
Wondering if anyone can provide some guidance on this