I have the 6400 and it does have the 161" wheelbase. I went ahead and bought the harness, which comes itself with extra wire for "accessories" that I may end up using. OlBlue is out of town, and I think I'll need his help, so it may be a few days before I start redoing the wiring. From the looks of the harness it appears quite generous. I'll let you guys know how it goes.
