I see guys tgat do it with the stacks on the kw or petes....but I just roll down my window and back up
It don't matter if you if you open your door, lean out the window, sing a little Willie Nelson or whatever. As long as you can get it where you want it without hitting anything it's all good.
I open the window and poke my head out so I don't have to listen to the CB rambozos bagging on the Swift driver backing up. When I started many years ago new drivers got to be the yard ape for six months before going on the road and that muscle memory came back when I started driving again. I land where I want 80% of the time without any pull ups which tends to stop the CB chatter so I can ask if anyone would like backing instructions.