While grinding on a set of heads for a friend today I noticed these "stamps". (right below the guide theres a "dash" indentation) We were discussing what they could have been for and I dont have an answer...Was it used as a guide to stamp where the guide punches through?
Just curious. Heads are 95 LT1 fwiw....and no, thery arent near "done" yet :boring:

http://img.photobucket.com/albums/v224/kalthoff1/lt1heads016.jpg

http://img.photobucket.com/albums/v224/kalthoff1/lt1heads018.jpg

just for the heck of it (still not done, btw)

http://img.photobucket.com/albums/v224/kalthoff1/lt1heads013.jpg

Looks like whats left over from the very first hole drilled into the valve pocket.

PS...thats got to be boring work...:thumbsup: