Rkymtn57
From what I've found, on 1785/1800 Dickert rifles, several have two parallel incised lines along the length of the forearm. They're cut pretty shallow and narrow. Not near as deep as the original rifle that Dave B showed. They're located in about the same place as that rifle has them, about in line with the ramrod thimble pins and a bit below the barrel pins.
Again from talking with owners and such, the muzzle cap is made in two pieces with the front end soldered on, and is held in place on the stock with one rivit, under the ramrod. At least one original rifle has what you might call a low profile cap, with a half round section in it to fit the ramrod. Although it's more like a quarter to a third of a circle, instead of a full half circle.
John