Installing trailer tail lights?

ive got this old trailer and it already has tail lights on it but i want to change those ones and put LED tail and indicator lights on instead, do i need to change my wiring set up that it already has to do that? i also want to put some lights (about 3) on the sides of the trailer like how you see on semi-trailer trucks, do i need to run different wiring than the tail lights as well? im not much of an auto electrician so would this be hard for me to do? also, when i buy all my lights do they come with instructions and all the wiring and stuff i need? thanksInstalling trailer tail lights?
You can use the existing wires as is. Connect the side (clearance) lights to the tail lights. Be sure to run the ground wire to the tail light itself for the best results. When you finish if the lights do weird %26amp; crazy things most likly it is because of a bad ground.Installing trailer tail lights?
wiring doesnt have to be changed just tail light housings and as far as putting luights on side if wires arenot there you would have to run wires but if you have sidemarker lights you can use them