I have converted my '32 chevy to all discs and a new power booster/MC combo mounted below the floorboard. All works good except occasionally the brake pedal will stay down after stopping. Can be pulled up manually. I have residual valves to install and have been told this will cure my problem. Does anyone know where I can find a 3/8" - 24 IFF to 1/8" NPT nipple so I can plumb the valves directly into the MC?