I have a 1994 Skamper slide in and the person who had before me replace truck wire connector with a regular two prong 120v connector like you find on an extension cord. It not polarized so could be connect backwards. What type on connector should this have on it. Camper also has clearance lights but not stop or turn signals in the back. Most trailer seem to have 7 prong but not sure in need one that big?