Swap the wires on the sending unit.
Tried it. Still no works. Does the exact same nothing on either setting.
Tried to drive it again today. Tranny is proper ****ed.
Will move in first gear fine. Won't shift on its own. I have to let off the throttle for it to shift. And then when it's in second it barely transfers any power. Like barely keeping at speed and I can hear whirring/revving happening when I apply throttle. So I think I'm going to have to sack up and swap in the th400.

