Help choose engine for my 68 Barracuda

..maybe a .030 over 318 (3.94) with a 3.58 stroke (360)would be the best "all round" build,
same as the Corvette LS performance platform.
..how did GM arrive at 3.94 x 3.62 stroke?

Slugs for the 3.58 stroke in a 318 bore are not cheap IF you can find them.