67 camaro brakes

[wannarun70]

My 19 year old son rescued his first project car last week a 67 camaro rs. Car has been sitting for at least 25yrs so of course all the brake fluid in the master is gone with that little bit of gook sitting on the bottom. Planning on changing master, wheel cylinders(2 are frozen) spring hardware and linings. Would you guys recommend changing the hoses(not cracked) and proportiong valve. Is the prop valve something you can take of and try to clean? Its a power 4 wheel drum car. Thanks, Mark