The "kits" sold by TOTW, Pecatonica River, and a number of other suppliers is not what most folks call a "kit".
To most folks a kit is something that has been machined and pretty much finished and only requires a small bit of work on their part to put together and finish.
The "kits" from TOTW etc. are actually a box of semi finished parts and none of them will just fit together.
For instance, the barrel usually does not have the breech plug installed or the sight dovetails milled. The underlugs that hold the stock to the barrel don't exist and of course the touchhole isn't there.
The butt plate, trigger guard and often, the sideplate are rough castings requiring filing, sanding and browning or blueing.
The stock is rough shaped but needs a lot of wood removed.
Even if it has the mortice for the lock, the lock won't fit without doing some final trimming.
The barrel mortice is usually a very tight fit that needs enlarging and the rear of the mortice where the breech plug and the rear of the barrel fit usually needs squaring up with a chisel.
The groove for the barrel tang won't be there and needs to be cut after the barrel is fitted.
All in all, you can figure on spending at least 120 hours and usually more like 160 hours to finish the gun.
If your ready for this much work, read the posts on our Gunbuilders Bench and buy a good book that describes what and how to put one of these guns together. There are several of them on the market.
I don't mean to scare off folks who want to build one of these guns. It's a fantastic hobby all by itself and you will end up with a unique gun that is far above anything you can buy from a factory but, I hate to see someone spend $500-$800 for a box of parts and then be intimidated by it and give up before they even start.
Oh, about the Tennessee offered by TOTW and Pecatonica River (who is usually less expensive).
These guns come with a Siler lock so the lock mortice is cut for it.
A Siler lock is an exceptionally good lock but if you care, it is the wrong style for a Tennessee.
If you don't care about the lock you can build a very nice rifle like this one: