First of all ..... welcome to FSM morstuf5 and an even bigger welcome back to modelling.
As for your whippet, I've never built one but this is how I would paint the tracks.
First an overall coat of gunmetal followed by successive drybrushings of rust then silver. Next I would burnish them with ground pencil lead. Finally I would dust them with pastel chalks along with the rest of the vehicle.
As for gluing them, CA glue should work just fine.
Enjoy the forums !!!
Happy Modelling and God Bless
Robert