Watch where you install that wire loom. Most of them are made from cheap polypropelyn and have a very low melting temperature. You could even start a fire inthe engine compartment if the melted plastic falls on any part of the exhaust. There are some that are meant for higher temperatures, but even those should not be used in close proximity to hot surfaces.
I don't know if anyone makes them out of Teflon or nylon as those would be high temperature resistant.