This has been gone over again and again here. Yes, I am just a registered user, have been for 10 years but am going to bite the bullet and upgrade shortly, maybe even tonight, to support the place...
OK, the long and short of it. I attended a Hammer-In in Old Washington back in...well, I don't remember the year. I believe it was the Spring of 2001. Clyde Fischer was there. He imparted this knowledge to us and he was sure to say that he got it from the guy that dyed the bone for Case.
Here is the straight scoop...or what Case does/did any way...as told by Clyde.
Use fresh bone. You can get a fresh shin bone from a slaughterhouse or butcher. Go ahead and cut it up to a bit oversize to what you are going to use. He used Ritz dye. Simmer (don't boil) for 2-3 hours and turn off the heat. Do not remove the bone. Let it sit overnight. The next day, simmer again for a couple of hours. Afterwards, use half ATF and half gasoline and coat each scale with it. Layer them in a box with newspaper in between for 3 weeks.
This works, folks. Just remember. DO NOT BOIL! Just simmer! If you boil it, it will crack!
Craig