Although I model Zm I have just ordered the components to try making multi coloured signals. 0805 smt LEDs , plasticard for signal plates and plastic I beams for uprights. The rest of the circuitry will be below board again using surface mount components hand soldered to small custom made pcbs.
Will be a while till I have a successful attempt to show people but is a work in progress.
Mike based in deepest Surrey
Posting most of the time from a mobile phone please excuse typos