The slant or the 318

I'm in a similar boat. I have a 65 Dart 273 and recently got a 64 Valiant slant 6. I want to try things with both, and will definitely keep the slant, even though a V-8 would drop in the K-frame. I had a slant for 20 yrs until stolen. Australians developed the slant into a racer. I am starting to look at neat parts from down under, like long runner aluminum intakes. My wife will like to drive the convertible, and is afraid of muscle cars, so upgrades must maintain driveability and be more for wow factor.