Well by the looks of it you have a bit of extra wire, I'd cut it close to the insulation enough to get it in a ring terminal, crimp and heat shrink tube the wire and over the wire part of the terminal and try routing it like the stock wire if not further from the manifold. Heat shrink tubing is really tough against heat. I use a soldering iron to shrink it with smaller wires, and direct contact with something hot enough to melt metal (soldering iron) doesn't immediately affect the tubing.