I am going to start restoring a Westinghouse double arm electro-pneumatic shunting signal. Actually there is little apart from the main post casting but many parts are identical to those of the single arm variety of which I have a couple so can be copied. One part that I can not find enough details of is the post cap/finial. Does anyone have a picture of one of these (or indeed a spare one!)? I'm not sure how widely these signals were used, I can only recall seeing one at Bolton West but I'm sure they more widely used. The single armed variety could be seen at Southport and Salisbury in relatively recent times.
Pete