This is kind of a tough one as I've seen three tractors and they were all slightly different. My current tractor it runs along the top of the engine and then is secured to the oil cooler tin via some sheet metal clips. From there it shoots straight to the double connector and then to the headlights. Others I have seen ran down the frame near the engine but no two were alike. Seems as though that wire is vulnerable to heat and other things so it often gets routed however the guy working on it routed it.
First, ty very much for your reply! Since no one was getting back to me, I just took into account where the harness branches to the coil ( much closer to the top of the engine than the bottom) and also my unit does have those metal clips on the oil cooler, Going this way has to be original, especially after looking very closely at the wire, with it having three wear marks basically lining up with where the metal clips are..