There was a thread recently about using the later MoPar V8 water outlet. To jump real quick to the end, it can be made to work fairly easily. I already new that the flathead six and V8's used the same gasket there so I was pretty sure the outlet bolt spacing would also be the same, but the proof is in the pudding. The real trick was sorting out a molded hose. Did some poking around on the internet cam thought I might have found one.
The two main parts used