I've been going through a small accumulation of early issues & came across a few Harding issues. I always like to take a REAL close look at this issue to see exactly what I might have. When it comes to the SC#613 I find insufficient information in the SC, blogs or other resources to definitively identify the SC#613. I have a perf gauge, use a 5x+ glass, read the descriptions & still left with a 99.9% not a 613 but it's that 00.1% that always leaves me wondering. Since the 613 is noted as a rotary press printing & printer's waste, I am wanting to confirm that the design dimensions measurement would determine that the 613 issue is mm taller than the flat press printing. I am going to reread the Stampsmarter section of this issue but need some guidance. I'm really not wanting to certify a 610-612. (I think there is a 613 on a post card framed hanging in the little bakery/café cross the street from the North Attleboro MA Post Office... really good coffee &). Anyway, I believe if I had some info on what else to look for I can put my 0.1% doubt to rest. I am working under the premise that it is not a SC#613.