I am going to install 2- 2700 Milliamp batteries in a plane. I want to also install dual switches, one for each battery. Doe's the battery have to be a certain distance from the RX? I am using a JR 9 CH, with one main, and 2 remotes RX"s. Also can the batteries be stacked, one on one protected with foam rubber and tied down or do they need to be how far apart? Need some input. Thanks