honestly, there really was no great skill in building this kit.
there are kits and then there are KITS. the key ingredient is the stock, which can vary from literally an outlined plank to one that this fully CNC inletted and mortised. that's what trad muzzleloader kits are all primarily about - the condition of stock. almost no one is a "gunmaker" these dayze, where custom guns are built by "stockmakers" simply because the barrel and lock are both pre-made. the furniture can be scratch built or pre-made as well. this comes down to one's level of crafting skills - and tooling. the offshore "screwdriver" kits are, for the most part, just that - only a screwdriver is required to put the parts together along with very minor fitting.
TVM and Jim Kibler kits have CNC machined and inletted stocks that will always require fitting, but the real hard work is done, and that's always about making a proper trad muzzleloader long gun stock. it will really pay to question kit makers about the stocks they're offering, and then assess that against yer abilities and tool chest.
if one has a desire to "build their own", but is unsure of their abilities and the tools required, the absolute best starting point is with a lyman/investarms kit gun. yes, a "screwdriver" kit, but there will be some minor fitting here and there, along with the opportunity to rasp/sand wood and apply a stain/finish. plus, some serious dollars would be saved to boot.
then there is the question of metal finishing - or not. i always choose not and prefer to allow the steel, iron and brass to honestly patina/relic on their own, as mostly was done back in the 18th century. but, if desired, it's another opportunity to get in some crafting knowledge.