Another option is to use or replace the master cyl. W/ a dual unit, put a hydroboost unit on the back of whichever master one chooses and do away with the whole hydrovac system, especially useful if going to a diesel engine w/ no vacuum, need to installs power steering pump for the hydroboost; that is what I am going to do.
Almost all gasoline engines are still using the hydrovac principles.. engine vacuum on a large diaphragm to increase hydraulic pressure to the brakes. The only real difference is that the vacuum chamber is part of the master cylinder, not remotely mounted.
Coupled with dual brake circuits its a very safe setup.
