I've seen the line swap done.
Guy calls me and says: got a new 300$ pump and motor.
Was a B*&^% hooking up and still not working right.
If all components are dismounted and loose , yes this is very possible. But with preformed tubings and all components mounted, it's really very hard to inadvertently connect tubes to the wrong hole on the VB. Even with the correct hole it's still a struggle and can easily stripped threads if not careful. Hence, recommend loosening the other end for a little wiggle play to get it started. Of course, that is just my own personal experience.