Again,almost right.The P-valve should be after the brake warning lamp.For the warning lamp to stay off, it needs to have the same pressure on both sides of it.
-I just thought of something; If your car still has the 9inch rear drums, you might not need a P-valve. Those things have so little power.They might be a good match to the disc fronts.
-However, if youre running the 10x2.5 brakes,you will need the P-valve. Unless youre also running 10inch wide or better rear tires.
