Hydroboost   What is Hydroboost? Hydroboost is a hydraulic brake booster that replaces your vacuum booster, it results in ~2-3x the braking pressure for the same amount of pedal pressure as vacuum operated brakes. It runs off of your power steering pump. It’s bolt in, four bolts at the firewall, four bolts from the Hydroboost mounting plate to the firewall spacer and then the hoses and the two bolts for your master cylinder if you wish to retain it. If you keep your master cylinder you don’t have to bleed your brakes and it saves you the cost of the master cylinder. (This only works on some year ranges.) The cheaper system is the Astro unit shipped with or without the master cylinder. For that you get the rod bushed to your pedal pin, a 3/8” barbed hose T-fitting and install tech, these items come with every setup as required (some applications don't require bushing the pedal rod). If you want the heavier duty and later '03+ model with the long accumulator it costs a little more and can be shipped with or without the master cylinder. The new version of the mounting assembly with a 6* angle built in is available from an associate. (Slightly different than pictured.) This replaces your aluminum firewall block on '74+ rigs and spaces the Hydroboost out on '73 down rigs. I also use that for custom applications on other rigs. When you've decided which Hydroboost you want I will put you in touch with the builder and tell you what size mounting assembly it uses. Or you could get a stainless spacer that fits between your firewall block and the Hydroboost on '74+ rigs, another associate makes those, and size varies with choice of Hydroboost. Hoses will cost you ~$50 at autozone and both will need to have the ends at the pump and box first bent to match. If you have flared fittings on your pump and box you need to cut off and remove the end at the box and pump along with the metric nut, next you would install the respective nut from your old brake line (smaller at the pump, larger at the box) and then re-flare the end. NAPA would charge about $10 to do the flaring if you don’t have the tools. You will also need to buy six 3/8” hose clamps for the return line and Howe Performance recommends using GM Goodwrench PN: 89020661 for power steering fluid. I recommend flushing the power steering system and making sure that all works again correctly prior to installing the Hydroboost and bleeding it, that helps to isolate any trouble and gives you all fresh fluid. If you want to source your own 3/8 barbed hose fitting for the return line you can find them at Plumbing Supply. If I sell you a Hydroboost I include one to save you running around trying to dig one up or paying shipping. Bleed your brake system if you've replaced the master cylinder, starting with bench bleeding the master cylinder, and do this with the engine off. Finally, follow the provided instructions on bleeding the Hydroboost. Note: It sounds like a lot but it's not bad really, just getting the nuts off firewall spacer under your pedal assembly is the worst of it and that is easier if you pull the nut and push the bolt over a lil so you can remove the brake pedal.  You can contact me through my eBay ads listed here.  Prices are listed there as well. More information is also posted in this forum.