Check out the EHeads I got on my site. They had slag left...hell basically all over. Was able to break it off with my fingers. After much dremel action they look ok...contacted em they said oh sorry bout that! Even sent em the evidence pictures... HAH! Also look around where they cut the spark plug hole. Filings there as well.
Basically they ARE NOT BOLT ON as it is advertised...
Good luck!
http://www.visualmktg.biz/transam78/