I remember the space tank itself - it was based on this Overlander, wasn't it?
It was a single-module Overlander with a very large gun as I remember.
It didn't quite have the charm of the Battletank but it was certainly impressive.
You're right though, what I'm thinking of must be the MEV. They sent it down to Mars and it makes quite an impact on the alien base.
Is there any sign of a Terrahawks blu-ray? Here we have the Fanderson site saying how it was converted for HD back in 2013 (some episodes anyway).
I don't see the point in them doing that if no-one can watch it, especially since the DVDs are actually from tape rather than film.
Dream big and bold and daring.