Mario answered the question about the kit. And my dealer answered my email to him this morning and his explanation was exactly what Mario said in regards to the kit. He also explained the differences in the older Zeagle/Apeks regs and the new Apeks regs. Here is what he said:
The differences in the OLD STYLE Zeagle regs and the NEW style Apeks regs are subtle, but substantial in my view. Changes made to the NEW Apeks regs (those sold after the start of 2000) are not available in the old style Zeagle regs (which were all supplied to Zeagle prior to october of 1999) differences include the shuttle valve spring, the shuttle valve, the counterbanance cylinder, and the high pressure spring in the first stages. In addition, the orings in the Apeks are made from a "new" material they
don't much talk about. We know they aren't butyal, silicone, or viton, but they don't talk much about what they actually are.