[jhv48]

Brent makes some valid points. Building a 347 from scratch does take more engine know-how than a 331 or stock 302. And then, you have a maxed out block. No room for future expansion.

Since you seem to like the cubes, how about buying a used 351 (they're everywhere) and upgrading heads and cam as time and $$$ permit. A lot more bang for the buck and you can always bore and stroke it to a 408 if you have the inclination.