I've never made buckboard bacon, but have cured a few hundred pounds of pork belly over the years, and have only ever used one "recipe", which would work perfectly fine for whatever meat you're trying to make. Mike243 goes into tremendous detail on nitrite concentrations, but I prefer a dry brine with no water, and I use grams to measure out my salt/sugar/pink salt concentration every time.
For mine, I use:
2.0% Kosher salt (I prefer Diamond Crystal flakes for this since they dissolve easier. But Mortons Kosher will be fine. So will sea salt or Himalayan Pink salt. Just don't use iodized table salt).
1.5% Dark Brown Sugar
0.25% Pink Curing Salt (sodium nitrite) --- Pink Curing Salt is NOT pink Himalayan salt
For buckboard bacon, assume you have a 3lb pork butt. 3lbs = 1,361 grams. Easy to convert your sale weight off the tag into grams.
From there, you need a kitchen scale. Mine is a 10lb scale. Work in grams, use a bowl, and zero out your weight on the scale.
0.25% by weight pink curing salt is 1,361 x 0.0025 = 3.4 grams. This is important as too much nitrite is considered toxic. Your pink salt number shouldn't exceed 5 grams, which often is about 1 teaspoon.
2.0% by weight Kosher Salt = 1,361 g * 0.020 = 27 grams
1.5% by weight dark brown sugar = 21 grams
That's the basic cure for anything I use. Pink Curing Salt is possibly available in the cooking section at Academy. If not, I use Butcher & Packer to order mine in
Butcher & Packer Pink Curing Salt. You'll pay more for shipping than you will for the actual salt. I keep it stored in a glass jar.
Seasoning for me is always red pepper flakes, chopped garlic (one clove per lb of meat), 2-3 large bay leaves rough torn up, and as much fresh ground pepper as my forearms will tolerate. Usually it amounts to about 10 grams of pepper.
Mix your cure up with the seasoning, and liberally apply. For a roast this size, you're easily going to fit into a gallon ziploc bag. Cover the meat well, then dump the entirety from the bowl into the bag. Roll it around and refrigerate. It's going to release a good bit of liquid, so move it around each day so that it gets well covered. You'll need every bit of 10 days in the fridge with this method. Might ought to plan on 14 just to be sure.
After it's cured, rinse off the granular stuff (shouldn't be much) and pick off the bay leaves. You're not going for pristine clean, just get the gritty off if you can. I like to re-apply more black pepper at this point. Let it rest in the fridge for a few hours, up to a whole day, on a rack over a pan. From there, smoke it. I like a 250° - 300° smoke for about 2 hours. Heavy smoke is good. Internal temp "should" get to 160°, but I don't typically worry about it. It'll get to at least 135°, and if you want, finish it in a 250° oven to finish.
Let it cool, and slice to your desired thickness. Since the meat is already cooked, you don't have the same "raw bacon" considerations as you would otherwise. I've found that cooking in a low-heat skillet is best because the higher heat will scorch the sugars.