The stock 4 bbl intake is designed for the Motorcraft 4350 carb. To fit anything else requires the right adapter or to modify a Quadrajet to square bore adapter. I imagine the 401 will run OK with a 2 bbl. You may want to start looking around for an Edelbrock Performer intake. That is the popular 4 bbl upgrade for 360/401.
.....and welcome to the forum!