What length rear end fits a stock plymouth Barracuda?

Thanks, I just felt like I was being blown off by pat answers. These are the kind of answers I wanted to hear. I have this great 8.25 rear end that I spent big bucks on and I'm not sure what wheels and axel combo to put together. The answer is get down and measure it! I have an 8.75 489? rear that I want to build but I don't know what to tell the machine shop to make it for length. I have a friend that has a built axel housing shortened and stiffened,with Dutchman axels for the 8.75, but think they are too short for my car. They measure only 51.375" from mounting face to mounting face. I think my stock 8.25 is about 56.5"? Trying to remember from last year. I used to have a better memory for these things - Must be OLDTIMERS! LOL. I want to get some wheels but I don't have the money to throw arround to make a mistake and buy something I can't use. Well, as we said at the shop, measure three times, cut once! Thanks again for the answers. I don't mean to offend anyone. My sincere appologies to all.