64 Barracuda rear end

I have a chance to buy a 64 6cyl , orignal gold on gold for good price. Going to drive tommorrow owner says has a 8 3/4 rear could this be factory . Auto floor shift car. Any more info to look for would be nice. I have some A-body knowledge own 340 duster. And 1st. car owned new was 68 formula s 383 car.