8 1/4 rear end questions

Being a newbie to all of this, I want to add a question to this thread regarding 8 1/4 rear end. I am in the proccess of getting a donor car (a 1976 Duster will be delivered this Saturday) and the owner tells me it has an 8 1/4 rear end on it. Now I have not confirmed this, nor have I even seen the car but in pictures only (I know you guys are shaking your heads on that one, but the car is located about 200 miles away and he is going to deliver it to me) I have told him that if it does not have what I want on it (8 1/4 rear end, front disc brakes) then I will refuse delivery and I will be out only $100 for his gas and time to deliver it.

Now on to the question, how can you tell if the rear end has suregrip or what gears are in it???

Thanks for any help!

John