One of the curious things about D6 Adventure is that there are no rules for martial arts. In fact the phrase "martial arts" isn't even mentioned anywhere in the rules. Instead you just have a Brawling skill to cover all types of unarmed combat. To compliment that there is a short menu of Combat Options that you can choose from: All-out, Grab, Lunge, Knockdown, trip, Push, Sweep, and Tackle. I suppose that would work OK. In fact, it kind of reminds me of the way Hero System handles combat. But it's quite a change from earlier editions of D6.
In D6 Star Wars© martial arts were handled in a rudimentary fashion. Your Brawling skill had two specialization options, boxing or martial arts. It didn't really add much to the game besides the name. That changed with the publication of Rules of Engagement: The Rebel Specforce Handbook. That supplement included an optional rule for Custom Martial Arts. For every 1D you improved in your skill you could choose from a long list of special hand-to-hand techniques. With techniques such as Blindfighting, Multiple Strikes, and Nerve Punch characters with the martial arts specialization started to really feel like kung fu fighters.
This system was modified in the DC Universe/D6 Legend rules. There was still a list of Close Combat Maneuvers like Bear Hug, Double Kick, or Haymaker that a character could choose from. But now Martial Arts was a separate skill and your character could specialize in particular maneuvers. In addition to that characters with a high Martial Arts skill gained extra actions. For every 2D in the skill you gained an extra action in addition to your normal action. Now characters with Martial Arts could fight off multiple foes using amazing techniques, just like a kung fu master.
I miss the martial arts rules from those earlier editions. I don't know why they dropped them from D6 Adventure and D6 Space. Luckily the games are similar enough that the rules can be ported to the newer edition without much trouble. It's worth the time it takes to come up with a house rule to let you deliver the Smash of the Six Beetles!