Power steering pulley diameter question

So it's a 65 Dart Gt, just put a later model 360 in it that I built but all the old power steering pump, brackets etc was for the older style motor. I got a federal pump and brackets and was told that the Saginaw and federal were the same keyway pulley. Is this right? I thought they were 7 inch as well. Summit says its 6 5/8 or something like that. Whatever I just want to get this thing on the road.