727 Question

Hello Guys
This may be a dumb question but here goes. Do all 727 transmissions have the same tail shaft? If not what sizes and lengths do they come in? I have a 74 duster with a 360 and a 727 that came out of a dodge r//v. I've installed a 8 3/4 suregrip and I now need to get a drive shaft for it. but what I see on line the measurements don't match up.
Any suggestions?

Thanks
Old School