Maybe for the Fact that "I can do it".
But I still think that the 454 with a head/cam swap will get nice numrbers near or pass a L18, and if drive ability is what you want get there a stand alone injection system !!!
There are tons of options.
I understand perfectly the new school in the old iron......I did one my self. (lsx454 in a 69 Camaro)
But in you case you are not throwing the stone that far !!! IMHO