I' thought about it when I had a real lumpy cam and the vacuum was too poor to run the brakes well. Never did it though. I Googled Hydro-Boost and found a fair amount of info though.
I'm putting it in the convertible right now. I have found a system made to bolt directly into 67-70 Mustangs and it looks really slick. I obviously can't tell you how it works yet, but I've driven late-model cars with the same system and it's excellent.
You route your pressure line from your p/s pump to the hydroboost unit, and then from there to your power steering. Both the hydroboost and the steering have a return line. That's pretty much it.
PM me if you want more info on this system -- I'm a dealer.
Thanks, I pulled one of these from a 70's Continental this weekend. Now I just need to figure out how to make lines and what kind of thread this and the MII rack fittings use to make them. Yours looks about as tight as my 67/460 is. Should be great though, I have this on my 97 Cobra. Mike