I had posted this in the "Engine & Transmission - 33 HotRod" section but doesn't seem like anyone has an answer.

I wanted to see if anyone knows what the part number is or where to find an original t-56 transmission (the one normally used with the kit). I'm also considering and hoping that the t-56 magnum will bolt up the same as the stock t-56, is this the case or will i run into problems? I'm aware of many people modifying the transmission tunnel and drive shaft but is there anything else that i have to worry about? any other insight, experience, words of wisdom about this would be great as well, thank you.