i needed to know if anyone knows how to tell the difference from a 9 inch rear end and a 8 inch? well i know what the 8 looks like but i need to know how to identify the 9 inch, and in more than just one way too. the car is a 1966 mustang so if anyone knows please help, thanks

 

9" info. Check it out.
http://www.quickperformance.com/ninecase.htm

 

If it is a stock 66, then you have the 8". Carizzna gave you a very good example of what to look for if an upgrade was added.

 

Very few people put 9" rearends under a mustang. I did only because I wanted the disk brakes and I had a I6 in my car.

 

For the most part, the rear hump in the middle is the easiest way to tell if it is a 9 incher...

 

it pretty easy to tell a 9" ..I have to say that's a great site..good work!

 

If you can get a socket with an extension on all the bolts holding it in, it's an 8". On a 9", you have to use a wrench on one of the bolts.