Hi,
I've seen Medad Hills guns with trigger plates and the nut arrangement. I suspect he did what was convenient at the time. During the Revolution, the gun manufacturing in Goshen, CT was extensive and included making all the parts when needed. At one point the Hills shop may have employed 28 workers. The Hills family settled in Goshen because the bog iron produced in nearby Salisbury, CT was of especially fine quality and they used it to make guns and tools. Medad's father was Benoni Hills who had been apprenticed to Ebenezer Pomeroy of that famous family of gun makers. Benoni trained his sons Medad and John. Medad was fully employed making guns throughout the French and Indian and Revolutionary wars. Gov. John Trumbull of CT issued to the Hill shop what may have been the very first contract for making muskets during the Rev War. Benoni and John apparently moved to nearby Winchester, CT before the Rev War and eventually John moved to Charlotte (pronounced Sha lot') after the war and made guns until his death in 1808. John was probably the first gunsmith working in Vermont. I think Medad died about the same time.
dave