Thank you, Lin!
I love sycamore! My father in law used to sing a song related to "sittin' in the shade of a sycamore tree". Maybe he just made it up, but it always sounded neat.
Steve- as the sycamore gets older, it will become more apparent which is the main trunk, then you can prune it. I think, give it another year or two and it will show you. It does not matter that the original tree was removed, this new tree has its own root system to be that full.