That looks like it will be a very nice car when it's finished. I have only seen one wide block Poly 318 and they really look different than what I'm used to. I bet you're really waiting to get enough time to get the 'Cuda going, but at least you're putting two other MoPars on the road before then.
I remember driving my cousin's '66 Valiant Signet with a 360/4-speed combo several years back. While the styling isn't my favorite, that little A-body could really move!
Definitely post some photos of your son's car when it's finished as well as your wife's '63 Valiant.