Engine 90 5.0 LX Spark Plug wire

Hey all.

I have BBK shorty headers and by cylinder 4, there are two bends of pipe really close to the wire. I have a booty on it but notice after driving around for a bit that wire off cylinder 4 will register 380-420 F.
Should I wrap the headers to keep the heat down?
Secondly, would this wire getting hot like that effect spark ?

Thanks all