On my 3 cylinder 4000 the end of the oil pressure switch looks like a flat round button. The connector on the end of the wire looks like a standard female spade connector that would slide onto a male rectangular spade, with one side open face with the edges of the other side curled around. To connect it to the oil pressure switch you lay it flat with the open face side of the connector on the wire facing toward the block and you slide it on from the side. I hope that makes sense. If you need a better explanation, I can take some pictures sometime over the weekend for you.