I'm having John Donelson build this rifle, and he works over the lockplate to make a faux J.Rupp (I just checked with him - it's the Chambers L-5 [whew!]- which has a huge backlog of orders). I'm having him copy Kindig #62 (that same p. 176 you noted) with a few variations (.54 cal, 44" bbl, iron buttplate, thimbles, guard). The inspiration will be all from that Rupp. That rifle has always made my socks roll up and down. We're scaling it up a bit for me; I'm 6'3". The Lehigh school is unique, but Christian Springs was only 20 miles away from town of Macungie, where the elder J.Rupp lived (he had a nephew, also J. Rupp, who was a gunsmith) and his older brother Herman Rupp - also a blacksmith and gunsmith according to the tax roles. The Moravians of Bethlemhem and Christian Springs were producing locks from 1740's to 1760's, and then the Molls, Nieharts and Rupps appear. J. Rupp probably made more than two guns, so I have taken the liberty of assuming his early work borrowed on the Christian Springs influence, and possibly even materials, before he had developed his unique style. Moll and Rupp may have apprentaced there, or one did and passed it on to the other. (I have seen one account of Rupp apprentacing to Moll, and another claims Moll apprentaced to Rupp?) This will be the imaginary, but possible, early J. Rupp piece (but with the signature J. Donelson on the barrel). I even talked John into retaining the Rupp hump under the bow extension - he preferred the Moll where it blends into the trigger bow better.