Unlike the kits made by folks like TC, Lyman and Traditions all of the kits from the small specialty muzzleloading companies are little more than a box of raw materials.
The locks and set triggers are assembled and function but they must have holes drilled and threaded into them in order to mount them into the gun.
The underribs will not have holes in them and there will not be any threaded holes in the barrel to attach them.
The trigger guards, butt plates and sometimes the sideplates are raw sand or investment castings.
The barrels from some companies like Green Mountain are threaded for a breech plug but it must bought seperately and installed by the builder.
Companies like Rice usually supply the breech plug fully installed in the barrel.
For what it's worth, the first 4 "kits" I built were done without a drill press.
I used an electric hand drill and some small combination squares to help me "eyeball" the angle of the drill bit while I was drilling.
Not easy but it is doable.
As for the under-rib, some folks don't screw them to the barrel. Instead, they solder them in place.
These "kits" can easily take up to 180 hours to finish.
That's not all bad. Once you build one you will want to build more.
When I started I could only afford to buy one kit per year so the large amount of time needed to finish it wasn't a problem. In fact, I couldn't afford to finish them any faster.