I built a 50 cal hawkins from a kit when I was in high school.
I bought a bluing kit from a gun shop, it was a lot of work and the results were poor at best. What I would recomend is to prep the barrel and get it ready for blueing then take it to a reputable gunsmith for the bluing process.
Another option is traditional "browning" and I understand that this is a much easier process for the do-it yourselfer???
I made my flinter from the same kit that you are considering. They sure do make a fine rifle. Bluing is a little bit more tricky than browning a barrel. First you have to degreese your barrel repeatedly. I used dish soap and hot water, over and over. When I thought it was done, I cleaned it one more time. Then I used a cold bluing kit and submerged the barrel. It turned out quit well.
Hunting can be slow and frustrating if Mother Nature throws a warm hunting season at you. But things can take a drastic turn for the better with the onset of a cold snap. Whether you get snow or just a good, prolonged cold front, the hunting can improve on a dime. But cold whether can also make certain parts of the hunt more tedious. Here are some things to keep in mind when your prayers for cold weather finally pay off.
You can see a your quarry's breath when it is cold outside...