I would consider rebuilding the dashboard from scratch if needed to achieve this... however the default for the two column gives me 4 places to put charts, after that they too will be stacked in the way shown below. I know this is a solvable problem because the pre-existing dashboard already has 7 charts with 6 of them side-by-side... but I can't seem to even do 6 side-by-side when starting from scratch...
I am not sure what I am missing with this, didn't expect layout was going to be my biggest issue!