This model was a strange last-minute pull by Chrysler. "Shit, we don't have a full-sized Dodge this year! Just grab a 1962 Newport from the Chrysler line, then put leftover 1961 Polara front clip on it. There, instant full-sizer!"
To their credit, they did a good job of refreshing the front and rear clip continually to make the early-'60s body look fairly fresh through '65.