I just put a set of tvs in my headrest. now i need to get them to work. what do i have to hook them up too on my headunit. theres 2 rca cables comin from each tv and a power and ground. ive gota kenwood dvd head unit with a 7inch screen. any help would be great. im thinkin i might have to get some kinda spilter to get them to work?