To add to my previous posting, I have the factory power brake booster in my 64 1/2 ton with automatic trans, and am in the process of converting from drums in the front to discs. I have been told I can use the existing booster add a dual outlet master cylinder and proportioning valve to do this, but it seems that the existing booster would not have the same output as a later one designed for discs. Anyone know if I can use the existing booster?