Instead of expensive heat resistent sleeves, on both my cars I took a 1 inch diameter
aluminum broom handle, and cut 3 to 4 inch sections out, and slipped them over the
plug boots and wires, near the headers.
Actually, you don't even have to unplug wires to put them on. Just cut them down the middle,
open them up, put them on, then crimp them back down.