Well, thanks for the comments.
Since my engraving skills are still even more undeveloped than my carving skills, I fumed the brass in a can with a cotton ball soaked in Ammonia for a few hours, & then rubbed it back The patchbox, I installed before I stained the stock with 1:5 ferric nitrate in distilled water, twice, followed of course by heating and then Dangler dark brown and reddish brown stains. which I rubbed back with steel wool and burnished with a steel and denim cloth. Then sealed with a heavy coat of Chambers Traditional Oil varnish and a second coat rubbed on. I then used some black spray paint on the patchbox and entry thimble and other areas where oxidatiionvetc. might accumulate. I blued the barrel and lock with Brownell's 44/40 creme three times...it was beautiful,,,,but looked too new so I applied two coats of Dangler's browning solution and let it sit for a couple of days in the humidity. It turned red, but when wiped back and oiled it turned a nice dark coffee brown. I burnished the stock between three more coats of varnish and rubbed back the wear areas a little more vigorously and then topped it off with a coat of Renaissance Wax. I wish I could get a good picture of the upper forestock, it is beautifully and regularly stripped from the entry pipe to the muzzle.. In the daylight more gold and stripe shows on the buttstock as well. I did try to leave some things a little irregular to add age, but just couldn't ding up the wood so much...I figure I will take care of that in the woods this fall.
My next gun is a .58 caliber Griffin rifle barrel in a figured plank of black walnut. I am thinking of using an early Ketland lock and making a very plain, almost barn gun to capitalize on the beauty of the wood. perhaps Griffin furniture so it would look more like a fowler, but be a rifle. I understand that is what Griffin did when he built a rifle.