EGT guages are not necessary when you have a wideband although some people still have them. I know just about everyone and their brother has a manifold that is taped for a egt that has a plug in it, I do.
Get this aem guage and harness, it has everything you will need and it's new,
http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWNX%3AIT
Secondly this is a DSM forum, not a mustang forum, mustangs suck! I would love to see the look on a mustang enthusiest face when he sees there is a chevy motor in the car. You should just throw a 4g63 in this thing, it would be cooler if you did.