YES!!
I am guessing this is on your 97' so here goes. The plug going into the gaskett from the outside, check it, if burnt at all you should get the repair kit from IH (like $30 or somthing like that) to repair that plug. You will have the gaskett taken care of so thats good. BUT, the under valvue cover wire harnesses you will need to replace one of them most likely because I am sure it melted one of them, but check both of them out. YES, replace all 4 plugs with the motocraft plugs NOT the Autolites from shucks, etc, they will crap out on you. This just happened to me not to long ago, while your in there might as well be replacing things out, I am pretty sure you will need to replace at least one of the under valve cover harnesses, just look at the plugs, if burnt replace, no need to try and "push" them and let er' happen again. Here is a link of my problem, a little more drastic then yours im sure
http://community.webshots.com/album/493256996kMAIgr