I'm not an electrical genius by any means so any assistance you can offer would be much appreciated! If I've posted this in the wrong section or I'm breaking any rules I apologize in advance 
So my situation is I'd like to make a modification to my truck to have a forward facing camera. Currently the truck has a reverse camera that only displays when in reverse, the problem with this function is I can only see the ball hitch when in reverse and if I need to pull forward to re-align I lose track of the orientation.
Ultimately I'd like to wire a switch into my dash where I could have three positions. When I press "up" I'd like the forward camera to display in my mirror, when I press "down" I'd like the rear camera to display and in the center position I'd like it to default to normal operation. Then in the "center" position it would operate normally. Default operation has a bypass wire so that it only comes on in reverse, I don't know if the wire only supplies power to the display when in reverse or if it supplies power to both camera and monitor when in reverse.
If I cant keep this functionality being able to manually turn on and off would be fine. They are 12v cameras so I'm assuming I can wire it into any existing 12v supply that comes on with the key on, I wouldn't want to be able to "forget" they were on and kill my battery. I require this for parking situations and monitoring how close my grill guard is to bump gates (If you're unfamiliar with the gate its simply held closed under tension and you "bump" it with your vehicle to get it open so you can drive through.)
What type of switch would I need and can anyone shed light on how I'd have to wire it? Also if more information is needed I will do what I can to supply it, thanks again!
So my situation is I'd like to make a modification to my truck to have a forward facing camera. Currently the truck has a reverse camera that only displays when in reverse, the problem with this function is I can only see the ball hitch when in reverse and if I need to pull forward to re-align I lose track of the orientation.
Ultimately I'd like to wire a switch into my dash where I could have three positions. When I press "up" I'd like the forward camera to display in my mirror, when I press "down" I'd like the rear camera to display and in the center position I'd like it to default to normal operation. Then in the "center" position it would operate normally. Default operation has a bypass wire so that it only comes on in reverse, I don't know if the wire only supplies power to the display when in reverse or if it supplies power to both camera and monitor when in reverse.
If I cant keep this functionality being able to manually turn on and off would be fine. They are 12v cameras so I'm assuming I can wire it into any existing 12v supply that comes on with the key on, I wouldn't want to be able to "forget" they were on and kill my battery. I require this for parking situations and monitoring how close my grill guard is to bump gates (If you're unfamiliar with the gate its simply held closed under tension and you "bump" it with your vehicle to get it open so you can drive through.)
What type of switch would I need and can anyone shed light on how I'd have to wire it? Also if more information is needed I will do what I can to supply it, thanks again!