Lots of ways to do that, but it depends on what your application is. Are you towing, or do you want to have a race truck? After that are you wanting to have a high hp screamer, or a torquey engine that tops out at 5000 rpms?
351w stroked to 408, AFR heads with a Trick Flow intake, some decent headers and you'll be close to or over the 400hp to the wheels. 351w are torquey motors.
a set of victor jr heads and a victor jr intake a 750 carb and or the victor jr fuel injected version. then of course a decent cam with around the .550 lift and bam 400+ ponies. of course ud pulleys windage tray electric fan etc etc etc.