I've seen a couple of videos,of the hydroboost swap. It looks quite complicated,especially for a "backyard mechanic",or novice. I drove an I.H.C. 1600,with a V-8 diesel,back in the mid '80's,and the brakes were electric assist. You touched the brake pedal,and the (brake assist),motor would automatically apply the brakes. If you needed 'em quicker,stomp the pedal,and the system would over-ride. I'm pretty sure the truck had a dual hydrovac set-up as well as a reservoir tank. If I can find a completer unit in a junkyard,for cheap enough,I'm thinking about going that route. It all depends on the bore,though.Without the volume,the cylinders aren't going to push enough fluid to stop a "Big Bolt". Not even at slow speeds on gravel,where you'd expect a wheel or two to grab and "lock-up".