has any one installed there own screns in the head rests and/or ther visors? i just want to know how diffucault it is. i plan to get a scion and put 2 jl w6sv2's(yes over kill but thats how i like it) in the back new speakers and screens in the head rest and visors when i get back from basic traning. and want to do as much as possable by my slef. so any one that can help thanks