My baseboard heater has its junction box built into it, meaning there are wire nuts in a section of the heater. However the ground has been broken off more interior / near the heating element. I need to cause it to reach the junction box so I can ground it. Is it safe to use a wire nut more inside the heater / nearer to the heating element? I think wire nuts are rated to 105C and a baseboard heater shouldn't be getting nearly that hot.
I would use a crimp ferrule the reason being the wire nut could melt and then create more problems the crimp is just a metal ring that connects the wires together nothing to melt. Years ago we had to use crimps in all the boxes for the grounds at least in the areas I worked.