Hello Regg...if you get a second, watch this video. In it he explains the parts in the system and how the Hydrovac works. He recommends two shops, Prior Automotive in Texas and Power Brake Sales in Sacramento CA for the rebuild. I called the one in CA and she said they will rebuild them for just over $300.00. Said just ship it to them with your contact Information and no problem (916)446-7829. After watching the video I've decided to keep my truck stock and repair the system.
Video:
All about the Bendix HydrovacGood luck bud.