I'm guessing you want to change the hose from POL, that's the male left hand thread to the QCC female right hand thread connector (big plastic one)
all new tanks I have seen still have POL inside, I wouldn't worry about changing the hose and regulator just for that
but if you want to anyway take the hose off, buy a new hose and you might need an adapter fitting at the manifold for that Weber, I think it will be 1/8" female pipe thread end by 3/8" male JIC
use pipe dope or gas approved thread tape on the pipe thread ends, but none is required on the JIC connection as it is a flared compression fitting