It's better to concentrate on the engraving, not the signatures. The forgers were often very good at copying manuscript signatures accurately. The engraving is inferior to the genuine, but not noticeably so, apart from the curved "Payable at...." which is poorly done. The easy giveaway is the spelling mistake, Mechanick's. Just to elaborate on the engraving a little, the end panels have lots of rows of little circles, which are fairly straight, uniform in size, and evenly spaced on the genuine, but not as well done on the counterfeit. The clouds etc. are also not copied exactly. I'll try to get back to you with some pictures if I can get my computer to work properly.