Hmmm...if Wikipedia is to be believed (and generally, it is...), then the artist for "Dark Dungeons" was Fred Carter, who drew many of the Chick tracts. See: http://en.wikipedia.org/wiki/Fred_Carter_%28artist%29
So, I guess I too stand corrected. I'd like to know if Carter was influenced by the Tribe or the Crusty Bunkers, though...there's definitely a South American feel to his art. I experience a rational disconnect looking at these tracts, as the quality of what I'm seeing and what I'm reading is at odds with each other.
I'm sure some enterprising soul out there could have fun doing a "Garfield Minus Garfield" with these comics.