Thanks for all the comments/opinions on this one. I was leaning towards a .54 cal to start with, but from reading various topics in the past, I don't see many using a straight barrel. The stock has good figure in it and would be a shame not to use. I just didn't know if anyone has ever tried to add thin slivers of wood to the sides/bottom of a channel and use a different barrel once one has already been cut. I'm not to worried about having a totally "correct" rifle as my skills aren't to the level to make one, even if I had all the "correct" parts. I have built a few rifles in the past and enjoy working on them and shooting them. As far as the iron butt plate not being correct, it's not a Tennessee style BP, but a copy of an early one, wide and flat, similar to what I have seen on quite a few brass-mounted rifles. This one is just iron/steel. Again, thanks for the input. All of the comments have pretty much re-affirmed what I was thinking of doing in the first place.