Old time GMC'ers look @ this, the car relate part is not the meat of this post.
I have a set of Cylinder heads that are off my convertible that are an upgrade for stangs. Anyways I got overzealous porting them a few years back and ruined one head hitting a water port.
I was googling the part # to see if I could find a used replacement so we can use them on a buddies car and I found this old link... Note the 4th post. It would seem our old pal was not only a gaming douche but doesn't know much about cars either...
http://forums.stangnet.com/517975-co...g-f1ze-aa.html