I love it when people trawl the archives and bring these beauties to our attention again. The idea of using the wound part of a guitar string to simulate the spring on the antenna has got to be the neatest and simplest way of doing this.
Great model, glad it was put up top again - I wasn't here yet in 2006.
The May issue of Hemmings Classic Car mag has two features on NYPD cars, including an ex-officer's re-creation of a 71 Plymouth. Worth a look.