Tim,
Not long ago we were discussing weak stamps on an early Syracuse Lefever 16 I had recently acquired. There were some questions about about an "F" stamp that also appeared to be a weak "E" upon closer inspection. Below is a link to that thread which shows some images of the Lefever and stamps.

http://doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=55707

O-D