Chris and Andy, thanks for your comments
Had a good look at the signal box today and although I'm not trying for an exact replica, I wasn't happy with the results. I don't know what it is but I don't think it looks right.
So, tonight, with different materials I started on another.
So far it's in kit form with other bits to be done before I put it all together.
Once I get to that stage the stairs will have to be made. As yet I haven't given this any thoughts.