Simple Man, I have used Braided Self Wrap PET Sleeving for 20+ years on the entire harness. It is good to 257 degrees and I never had trouble with it in an engine bay. One hundred foot rolls are available from DelCity.net in various widths, #851,#852,#854,#855,#856. If you are not already familiar with DelCity.net, they are a great resource for all things electrical.