Does the polarity of this connector matter? I think I plugged it in the other way round. The wedged side outwards, smooth flat side inwards.
Although this guy in the video could have it reversed? (his wires are opposite to mine)
Damn should have taken a photo of it before unplugging.
*edit - I think I found the answer. In the same video there's a shot of the fuel gauge being removed. So I need to remove mine again and check the polarity is the same as here. I think mine is the wrong way round.