I am using the stock '69 Scout 800 prop valve??? Not sure exactly what it is but its mounted on the firewall, brakelines go into it and out to the wheel brakes. The Chevy h-boost has o-ring fittings and my pump/steering box has flared fittings. I only used the hydroboost and bought all the lines,fittings, and adapters from psc. I also bought a psc pump with a remote reservoir and mounting bracket from IH Parts America. The mount doesn't fit the Scout 800 with the sii steering box but can simply be modified to fit. I scrapped the abs crap from the Chevy. The hydroboost cost me $50 from the local wrecker, I removed it myself, but I didn't take the pump. I am sure the stock pump would work fine for steering and brakes but I upgraded to the psc unit so I can add hydro assist later. Just need the plumbed steering box and ram etc... You can look in the store to get a price on the pump, the plumbing lines, adapters and fittings from psc added up but saved alot of headaches since nobody around here had a clue as to what fittings and adapters to use. After two days and approx. 16 different hydraulic shops I just got on the phone and talked to psc, they hooked me up and new exactly what I needed. Not sure what IH Parts America has in the store for fittings, but I am sure they have what it needed to get it done also. The brakes are awsome, the rears tend to lock up a little soon, but really not an issue. I am not impressed with the brakes when the motor isn't running. I have two barrell Holley that doesn't carburate worth crap. Seriously looking into the ez ei from fast. Pricey but very cool. Still doesn't help the poor brakes when stalled but would cut down on the stalling on hills...