BTW, it sounds like you will have the strongest, most durable parts from the git go...finding that cylinder and barrel was quite a coup!

The barrel mounted sight... will the base for that be soldered on, or what? Back in the day, S&W used to make "half target" versions with the base for an interchangeable sight blade forged into the barrel... changing the blade allowed elevation adjustments. Also, you might consider adding the FDL Wondersight if you want fully adjustable sights. If your donor receiver is old enough to have the 4th (top) screw on the side plate, no alteration is necessary. Later receivers require drilling and tapping that single top screw hole for mounting. just a thought... I have one I plan on using on my original 1916 vintage 32-20 M&P some day.

Froggie