I have a 350 and im going to install dynomax ceramic headers, i currently have MSD helicore 8mm plugs and wires that run together along the bottom of the valve cover. Will the wires melt? What do i use to protect them? thanks

As long as you have an air gap of 1/2" or more you will be fine. 1/4" may be OK but anything closer will probably damage the wire eventually.

Troy.