if you've built guns before, you're well aware that this isn't a screwdriver- ready project. If not, i would rent the video, and also check out American Pioneer's website. If you can get a copy of The Gunsmith of Grenville County by Peter Alexander, and a copy of Recreating the American Longrifle by Shumway, you will have spent the better end of a hundred bucks, which sounds like a lot, but really is pretty reasonable if you consider the cost of the parts you didn't ruin, and the value of the time you didn't waste, because you had the knowledge imparted in these books. (Not to count the embarrasment, the frustration, the time in purgatory for all those cuss words- if you believe in purgatory and all that stuff, and the blood you'll have to clean up off the shop floor.)
If you're renting videos, and you can't already sharpen a chisel to shave- your- forearm- hair sharp, you should develope this skill before you do anything else.
Just one guy's free advice, and no doubt worth every penny.
good luck with your project, and make good smoke!
(p.s. - i'd go for the 20 gua / .62 calibre smoothie, but the question of rifle or smooth is sorta like asking what's the best pair of shoes- every answer is correct, but every answer is different)