68 Cuda 383 vs a 360
For a mild driver 360 all day long.
I went thru a similar decision making process about 5 years ago when I started redoing my 69 cuda. I had equal amount of parts between BB and SB stuff, but ultimately decided on a 360. I've had 383s before and have never been overly impressed with the power they make for a Big block. After having a 440 in a duster with TTI headers and working on SB stuff, to me the 360 is lighter, easier to work on, and if you want some extra power than just stroke it.