Back when I was working on converting to EFI, I had thought of going this route, and using a single throttle body. But the end cost would be higher, it would be a lot more work and there is a good chance it would not work as well as 4 carbs. So I stayed with the idea of converting the 4 carbs into 4 throttle bodies.
I can relate to that welding.
If I went by that theory I would have gone thru a lot of bullets by now. I can weld, I do not do enough welding to stay in practice, A lot of my welding is not pretty but it is solid and functional. By the end of a long project it does start to look much better, but then I wont weld anything for a year and the skills deteriorate again.