The first "Space Tank" model I ever stumbled upon, and still a favorite, is the Paramount Astro Car.
It was a fairly detailed kit and the climbing wheels actually worked (something that couldn't be said for some of the treaded tanks).
I got this one in 1969 at a junky department store, along with other Paramount kits such as the Meteor, the Mercury, the Space Command Tank, and the elusive Barracuda Hydro Tank. The Astro Car is the only one I saved, unfortunately.
I originally tried to paint it in camouflouge, as in the box art, but it looked so crummy I painted over it with black primer. My plan was to then paint on a nice metallic blue top coat, but as you can see I never got around to it, so it remains in basic black.
I also replaced the deteriorated rubber treads with some Tamiya replacement treads. As most SF toy fans know by now, this is actually the Midori Super Beetle, a very popular kit which was reissued many times and was also the basis for several popular space toys.
This beauty now resides at the Arima Toys & Automata Museum in Kobe, Japan.