probably old post and beam, i had one about the same age, sometimes they didnt always follow what we call code. I tell you what though, my floors were unlevel and slanted, I peeled back the years of renovations and the original beams were square and level. They really knew how to build them, and the true lumber, wow, boards 26inches wide, over an inch thick and 14 ft long.

i know a few sinks I have bought come with a reasonably long plastic socket. A crow foot wrench could do it. If you are not reusing the faucet, could maybe just break the bolt. Thinking thin nose vice grips should get you started enough to finish by hand

isnt it a 5 speaker system 2 front, 2 rear and 1 center