I put together a comparison of my Snider GPC from 1951 with your signature, mine is the one on top. It could be different since there is a four year gap, but I'm pretty sure mine is legit and yours looks different to me, both in the slant and letter formation. Charlie was good at this, but often he didn't really form the letters fully, just made them kind of loopy. I think that is what you have.
snider comp.jpg