I like Atomic Highway, and though I know the final supplement of Gunmetal Road is supposed to include cybernetics, updates on the document are patchy due to the author's life circumstances (which I don't blame him for.) So here is a suggested simple cybernetic system to use until the official rules are out! Weee!
Any character can generally have cybernetic parts, even mutated plants. Cybernetic parts can range from x-ray eyes to bionic limbs and more.
If you have cybernetic parts, you must take the Flaw: Cybe. Like the Mutie flaw, the Cybe flaw will cast you in an unfavorable light with some people. If you're both a Mutie and a Cybe, good luck.
A piece of cybernetics can either take the form of a regular piece of equipment or a mutation. A character can only ever have a number of cybernetics up to their Toughness score. Cybernetics are basically "willful" mutations you have installed, and better yet, having one does not require you to take a balancing flaw.
There are drawbacks, however. For every certain percentage of your health you lose, one of your cybernetics ceases to function. The amount of health depends on how many modifications you have. If you have only one, it stops working at half health. If you have two, each stops working when you lose 1/3 of your health and so on. They will come back online once you heal, but being injured could very well leave you short a needed weapon or ability.
Further, cybernetics are hard to find and hard to install. Trading for one usually involves some kind of large favor or task, not just a simple pile of junk. The mod may also not be exactly what you're looking for.
To install the mod, you have to have someone else do it. The procedure usually takes a day, and at the end of the operation, the character must make a Toughness test. If they pass, the surgery took and you have a shiny new robo-arm. If you failed, your body rejected the implant and you have wasted your money, time and probably a body part. Feel free to increase the difficulty of the test if the mod is powerful or the doctor was a butcher.