I used a Progressive Dynamics 4045, but it wasn't an easy swap out. It mounts to a vertical surface and needs some ventilation. I have also added some 110 outlets and
lights, plus some 12 volt
lights, so I've done a lot of new wiring. I also rewired the
tail lights. Check your tail
light wiring cords , mainly where they exit the tongue underneath, ours were cracked down to bare wire.