This chart shows that even with balanced props, there is a sweet spot for mounting that will provide a minimum vibration level. Without testing, it is very unlikely that a low vibration will be achieved and most likely the number will be at least two times greater than the minimum. It could even be much worse. One of the five motor/prop combination had more than 6 times times the minimum vibration for some prop positions and more than 4 times as much even just 45 degrees away from the minimum position!
It typically takes about 10 mins per motor/prop to find the minimum so it adds a bit of time to my quad builds. Since I'm somewhat obsessed with getting low vibration performance with my quads, I think it is worth the effort.
rc-connectors.com has just about every small connector ever made, nicely arranged by model. For example, here's a SMD nan-JST female 3-pin right angle piece. Just what you need to make a green dot vapor brick AR6400 compatible!