I will PM you a link to a wiring diagram, although it's easy enough to use any multi meter and find out what's what. The plug is a POS, yes, but if you intend to use that receptacle you will have to use that plug as it's CFM only.
Yes, it says 15W40. But you can use 0,5,10 or 15w40. Just make sure it's no heavier and that it has the JASO MA rating for the wet clutch.