[6pack] Numbers Painted on the Block - John Mac?

[John Cyganowski]

Hi All-

After having my block cleaned for a rebuild, I noticed these numbers written 
on the side of the block in organge paint.  Anybody know that these 
signified?  John Mac?

http://s465.photobucket.com/albums/rr13/cygan_06/?action=view&current=IMG_0651.jpg

John Cyg