This particular column, written by then line developer Dale Donovan, talks about making the game more grim and gritty. This was actually a common complaint of the game among players at the time. The era not long after the Marvel Super-Heroes game originally came out saw a darkening of comic book super-heroes, and their stories. Frank Miller's classic Daredevil run for Marvel Comics was one of the inspirations for this article.
The rules are pretty simple, and mostly boil down to retasking already existing rules (which is the best way to do variants).
This is what the article suggested that you change to the Karma rules in the role-playing game:
Continue to use Karma as described in the rules. This will, in most cases, keep the level of mortality about the same as in other Marvel campaigns, if that is what you wish. Good role playing though, especially in a grim setting, will sometimes result in a hero giving up his Karma to kill a particularly dastardly foe. In the Born Again story line in the Daredevil comic a few years back, the Kingpin of Crime methodically destroys Matt Murdock's life after he discovers that Murdock is Daredevil. If Daredevil had been a PC hero in my campaign, I probably wouldn't have objected if Daredevil had killed Kingpin in retaliation, especially if the PC Daredevil was role played as mentally unhinged as the comic's Daredevil was.
Use the villain Karma rules (page 20, Advanced Set Judge's Book) regarding killing the underlings of "master criminals." PCs would lose 30 Karma points for each henchman, underling, or goon working for the main villain who is killed, instead of all their Karma. After all, the thugs aren't important; it's stopping the villain that's the goal. And, if some goons get in your way, too bad—they probably deserved it anyway. All other normal Karma rules apply, though exceptions, like the Daredevil example above, would still be possible.
Play the PCs as outright villains. Again, this is not recommended, as it's not in the heroic tradition of the comics or the game, but I can see where it might be fun to play your favorite Marvel villain and trash the Avengers or the X-Men. Use all the villain rules in the Advanced Set Judge's Book, pages 19-21. These rules are intended to help the GM run his NPC villains, but you can easily apply them to PCs as well. This means that PCs would gain Karma for committing crimes, beating up heroes, putting those defeated heroes
in deathtraps, etc.
I know that there are still a number of people playing the original Marvel Super-Heroes Roleplaying Game around the world, games still pop up on Google+ from time to time, so these variants may be useful to players/GMs in those games. They can also be useful for players of the 4C RPG as well.
You can download a PDF version of the article here.