[Tx Firefighter]

I've never swapped the boosters. Just master cylinder out. Yes, all hard lines including prop valve. The prop valve mounts down below the radiator on the later trucks. You'll find when you drop the lines in place, it will nestle right onto the little crossmember under there on your truck. You'll need to drill two holes to mount it in place.

I usually unbolt the lines from the master cylinder and on each frame rail where they go through for the front brake hoses (3/8" flare nut crowfoot works best for those). Then unbolt the prop valve and lift the entire spaghetti out as a unit. Then drop into place on your old truck.

You'll see where the brake lines go through the left and right frame rails. The prop valve will lay in place on the little crossmember under the radiator. Drill holes and bolt it down. Use 73-87 front brake hoses. It's the easiest way I've found and uses those good GM formed brake lines.

It's best if you get the line that runs to the rear brakes also. It runs from prop valve and across and down the right frame rail. There is a coupler junction part way down the frame rail where you can disconnect it.