Hi,
TRS stocks vary in quality of the machine inletting. I think they have improved after making their most recent move. I have a Ferguson parts set right now that looks pretty good but had a British light infantry carbine a few years ago on which the precarved stock looked to be done by a 10-year old with a router. However, it was salvageable and made a good gun. I think the Track kit was originally by TRS. The TOW kit is a pattern 1742 Brown Bess with a lock marked 1746. You should understand that the dates on the locks have no bearing on when the musket was made or issued and do not designate any model or pattern. They simply designate when the lock was made and often the contractor's name. British ordnance often stored them for years before setting them up on a musket. Unfortunately, I do not believe TOW sells that kit anymore. It pays to know something about Brown Besses if you want to have one. The pattern 1730s and 1730/40s have stocks with the most drop at heel making them the most comfortable shooters. The pattern 1742 is massive but still has a bit of drop at heel. The pattern 1748 also has decent drop and is lighter and slimmer being fitted with a steel rammer. With the pattern 1756, stocks got straighter with less drop. That is particularly true with the later short land patterns after 1769. I have trouble getting my cheek down on them.
dave