I have that kit, and even if the decals were new, they were pretty crummy. The "gold" is not very gold at all. I found a dry transfer set of gold lettering in a style that is pretty close to proper. That has taken care of the lettering. For the striping I am trying to use a gold fine point marking pen on decal paper. It is going to take a little practice making lines of constant width and sharp edges, but I am working on it.
Scanning the kit decals and trying to reproduce them will not make a decent gold color. The available inks in an inkjet printer just do not reproduce metallic colors well enough (metal colors have a particular sheen- directional reflectivity- that inkjet inks just do not have. Those old fire engines were kept in pristine condition, so blaming the lack of that sheen on weathered service just doesn't cut it with a kit like that :-)