Be cautious on the location 'within the building'. Unprotected, unfused, conductors within a building, the distance allowed is not specific in the NEC. For the most part, it's left up to the local AHJ. I hear 12", 5', 3'4", but there is NO distance within the book & never was.
A main inside is accepted 'nearest to the point of entry', unless we use the 2" of concrete/brick exception. It all boils down to the AHJ's 'nearest' definition