I loosened a bolt connecting an electrical wire to my radiator today because I thought it was limiting the movement of the radiator as I wanted to change the front plug. I loosened the nut a little and it didnt seem to want to budge anymore so forgot that idea and managed to move the radiator without it.
I commenced in moving the radiator forwards to gain access to the front plug, changed it and then bolted all the bolts back on. However, now there is a leak on the nut I had earlier loosened on the radiator and a green liquid slowly leaks out upon starting the engine.
I have included a few photos of the nut I am talking about and wondered where I could get a replacement? Am I right in thinking it is the thermostat switch wire? Will I be able to replace just the nut or will I require an whole new part??
P.S: Yes I know I'm a complete plonker for not undoing the nut properly in the first place. I've totally messed up the thread on it and it won't tighten

Really needed my bike for the morning but can't ride it with it leaking antifreeze like this