Are you missing the Hydrovac completely? I couldn't rebuild mine because the end cap was broken. I had to buy a new unit. You can get one at http://vehiclesofvictory.com/. I had to change the two fittings, the inlet and outlet because they were not the same size, but that was no problem. Just be sure that when you remove them you don't let the lubricant leak out.

A day without laughter is a day wasted- Charlie Chaplin
When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired.
1948 Chevy 2-Ton