Me too. Fancy wood and all the upgrades from 20 years ago. Unfortunately he had inlet the breech and tang (quite well, I might add) and didn't know to reshape the tail and thin the square, flared tang first, so I had to get creative with a carving design. I also had to set the barrel back and shorten the tang 3/16" so the flash hole would clear the breech plug.
I mention this because I was advised by a friend to buy a Kibler kit for my first "build" so that I would learn the PROPER relationship of all the parts to each other before trying to figure it out on my own, and that turned out to be sage advice that I would pass on to anyone else starting out. I read the usual recommended books and built several from boards after that without issue. Then I did the pre-inlet Haines kit from Track and have ZERO interest in precarved/pre-inlet kits after that. Things are not put in the right place and aren't quite the right shape, but you're mostly stuck with it. More trouble than it's worth to work from a pre-inlet unless it has a return address on the shipping label that starts with "Jim Kibler".
I haven't assembled kits from Clay or Jim Chambers so I can't speak to those, they may be just fine but will definitely need inletting and shaping skills and an array of tool to finish.
If Kibler doesn't offer the style you want, buy one of his kits anyway and put it together. Watch his assembly videos. Buy a copy of "recreating the American longrifle" and read it thoroughly. By then you will have most of the knowledge and some of the tools needed to make what you really want from scratch. You will be able to buy a board, lock, barrel, and all of the hardware and furniture needed from wherever you can find them because you will have already had your hands on every piece required to make a longrifle and know what is required. The book will show you the tools needed to put it all together.
Avoid Sitting Fox at all hazards.
