Listen up Doug, I was the first to say that I was no Fox expert, I'm just saying that your Fox's checkering doesnt look "right" for that era of Fox. If yours is original, then it would be the first Philly Fox Sterly I've ever seen with pointed up checkering and with diamonds cut at that angle. The only Fox's I've seen out of Philly with pointed checkering were graded guns. I haven't seen a ton of em, but a few. Just sayin'.
We really should start another thread on this so guys like Researcher, ellenbr, Petrov, etc. can chime in, those are the guys that should be looking at this and telling us whats what.
Just thought of this and it has nothing to do with your Fox really, but that 30's era Sterly you mention, the one that letters with ugraded wood and checkering...why would someone do that? Why not just upgrade to an A grade gun?? Food for thought.

Dustin