hi tank i just the signal light and dual tail lights on my 56 stepside.i do beleive the 3 prong flasher is what gives you signal lights and 4way. iwill know tonight as i just have to hook up flasher and try everything. you will need a flasher and plug, as the clamp on switch does not come with these items.you will have to do the dual element socket for the lights as well.hope this helps some smile