Without seeing the kits it is impossible to know how much work will be involved. I have sold and built kits. Some are drop in easy to make but these are fairly rare on the market. Most claim to be drop in but require opening the barrel channel, doing inletting to relive the lock plate opening, drilling for barrel retainer pins and much more.
I am surprised that as an ML instructor you are not familiar with the fact most traditional ml guns were browned, not blued. (blueing existed but was not common) Why all this talk about blueing? If you are going traditional, go traditional.
I hope your kits are easy to put together or assemble. Do consider browining. Check with advertisers in Muzzle Blasts the publication of the National Muzzle Loading Rifle Association for sources for materials. If you want I can recommend several.