Your diesel should run between 80-85C. It if runs over 95C, it is not healthy for the engine. This might cool it down 5C unless you have major problems like cylinder head crack or leaking head gasket.
If you are installing our NEW injectors, these wires are a good option if your old wire plugs are rotten and breaking up. These will need to be wired into your existing harness.
Part of Kent's $8 troubleshooting and repair video collection. The video will only cost $8 but you could save $ hundreds and much grief by watching this video.