The person on the left uses his right hand on the left handle side of the centre Y stick.... and the person on the right uses their left hand on the right handle side of the centre Y stick. :>)   "Sorry" I could not resist...too much coffee this morning. I admit it was different adjusting to the centre Y stick, I flew at first with my hand around the neck of the Y like the familiar "joy stick" I was used to flying....after about 3 - 5 hrs you get used to the Y stick. I instruct a fair amount and find it works quite well in that enviroment. In normal cruise ...elbow on the centre console my hand usually rests in the cradle (top centre) of the Y stick..with all controls at my finger tips. It is actually very comfortable. I fly a 2005 CH601HD and a 2010 CH750 both with the centre Y stick...getting in and of a CH750 with centre sticks is like a Yoga routine. I recommend you fly the centre Y stick before complicating your build. IMHO